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* Teach zpool scrub to scrub only blocks in error logGeorge Amanakis2023-05-181-0/+3
| | | | | | | | | | | | | | | | Added a flag '-e' in zpool scrub to scrub only blocks in error log. A user can pause, resume and cancel the error scrub by passing additional command line arguments -p -s just like a regular scrub. This involves adding a new flag, creating new libzfs interfaces, a new ioctl, and the actual iteration and read-issuing logic. Error scrubbing is executed in multiple txg to make sure pool performance is not affected. Reviewed-by: Brian Behlendorf <[email protected]> Reviewed-by: Tony Hutter <[email protected]> Co-authored-by: TulsiJain [email protected] Signed-off-by: George Amanakis <[email protected]> Closes #8995 Closes #12355
* vdev: expose zfs_vdev_max_ms_shift as a module parameterRob N2023-04-061-1/+4
| | | | | | | | | Reviewed-by: Brian Behlendorf <[email protected]> Reviewed-by: Tino Reichardt <[email protected]> Reviewed-by: Alexander Motin <[email protected]> Signed-off-by: Rob Norris <[email protected]> Sponsored-by: Klara, Inc. Sponsored-by: Seagate Technology LLC Closes #14719
* vdev: expose zfs_vdev_def_queue_depth as a module parameterRob N2023-04-061-0/+5
| | | | | | | | | | | It was previously available only to FreeBSD. Reviewed-by: Brian Behlendorf <[email protected]> Reviewed-by: Tino Reichardt <[email protected]> Reviewed-by: Alexander Motin <[email protected]> Signed-off-by: Rob Norris <[email protected]> Sponsored-by: Klara, Inc. Sponsored-by: Seagate Technology LLC Closes #14718
* More adaptive ARC evictionAlexander Motin2023-03-081-78/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Traditionally ARC adaptation was limited to MRU/MFU distribution. But for years people with metadata-centric workload demanded mechanisms to also manage data/metadata distribution, that in original ZFS was just a FIFO. As result ZFS effectively got separate states for data and metadata, minimum and maximum metadata limits etc, but it all required manual tuning, was not adaptive and in its heart remained a bad FIFO. This change removes most of existing eviction logic, rewriting it from scratch. This makes MRU/MFU adaptation individual for data and meta- data, same as the distribution between data and metadata themselves. Since most of required states separation was already done, it only required to make arcs_size state field specific per data/metadata. The adaptation logic is still based on previous concept of ghost hits, just now it balances ARC capacity between 4 states: MRU data, MRU metadata, MFU data and MFU metadata. To simplify arc_c changes instead of arc_p measured in bytes, this code uses 3 variable arc_meta, arc_pd and arc_pm, representing ARC balance between metadata and data, MRU and MFU for data, and MRU and MFU for metadata respectively as 32-bit fixed point fractions. Since we care about the math result only when need to evict, this moves all the logic from arc_adapt() to arc_evict(), that reduces per-block overhead, since per-block operations are limited to stats collection, now moved from arc_adapt() to arc_access() and using cheaper wmsums. This also allows to remove ugly ARC_HDR_DO_ADAPT flag from many places. This change also removes number of metadata specific tunables, part of which were actually not functioning correctly, since not all metadata are equal and some (like L2ARC headers) are not really evictable. Instead it introduced single opaque knob zfs_arc_meta_balance, tuning ARC's reaction on ghost hits, allowing administrator give more or less preference to metadata without setting strict limits. Some of old code parts like arc_evict_meta() are just removed, because since introduction of ABD ARC they really make no sense: only headers referenced by small number of buffers are not evictable, and they are really not evictable no matter what this code do. Instead just call arc_prune_async() if too much metadata appear not evictable. Reviewed-by: Brian Behlendorf <[email protected]> Reviewed-by: Allan Jude <[email protected]> Signed-off-by: Alexander Motin <[email protected]> Sponsored by: iXsystems, Inc. Closes #14359
* Increase default zfs_rebuild_vdev_limit to 64MBBrian Behlendorf2023-01-271-1/+1
| | | | | | | | | | | | | | | | | | | When testing distributed rebuild performance with more capable hardware it was observed than increasing the zfs_rebuild_vdev_limit to 64M reduced the rebuild time by 17%. Beyond 64MB there was some improvement (~2%) but it was not significant when weighed against the increased memory usage. Memory usage is capped at 1/4 of arc_c_max. Additionally, vr_bytes_inflight_max has been moved so it's updated per-metaslab to allow the size to be adjust while a rebuild is running. Reviewed-by: Akash B <[email protected]> Reviewed-by: Tony Nguyen <[email protected]> Reviewed-by: Alexander Motin <[email protected]> Signed-off-by: Brian Behlendorf <[email protected]> Closes #14428
* Increase default zfs_scan_vdev_limit to 16MBBrian Behlendorf2023-01-271-1/+1
| | | | | | | | | | | | | | | | | | | For HDD based pools the default zfs_scan_vdev_limit of 4M per-vdev can significantly limit the maximum scrub performance. Increasing the default to 16M can double the scrub speed from 80 MB/s per disk to 160 MB/s per disk. This does increase the memory footprint during scrub/resilver but given the performance win this is a reasonable trade off. Memory usage is capped at 1/4 of arc_c_max. Note that number of outstanding I/Os has not changed and is still limited by zfs_vdev_scrub_max_active. Reviewed-by: Akash B <[email protected]> Reviewed-by: Tony Nguyen <[email protected]> Reviewed-by: Alexander Motin <[email protected]> Signed-off-by: Brian Behlendorf <[email protected]> Closes #14428
* Improve resilver ETAsBrian Behlendorf2023-01-251-0/+7
| | | | | | | | | | | | | | | | | | | | | | When resilvering the estimated time remaining is calculated using the average issue rate over the current pass. Where the current pass starts when a scan was started, or restarted, if the pool was exported/imported. For dRAID pools in particular this can result in wildly optimistic estimates since the issue rate will be very high while scanning when non-degraded regions of the pool are scanned. Once repair I/O starts being issued performance drops to a realistic number but the estimated performance is still significantly skewed. To address this we redefine a pass such that it starts after a scanning phase completes so the issue rate is more reflective of recent performance. Additionally, the zfs_scan_report_txgs module option can be set to reset the pass statistics more often. Reviewed-by: Akash B <[email protected]> Reviewed-by: Tony Hutter <[email protected]> Signed-off-by: Brian Behlendorf <[email protected]> Closes #14410
* Introduce minimal ZIL block commit delayAlexander Motin2023-01-241-0/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Despite all optimizations, tests on actual hardware show that FreeBSD kernel can't sleep for less then ~2us. Similar tests on Linux show ~50us delay at least from nanosleep() (haven't tested inside kernel). It means that on very fast log device ZIL may not be able to satisfy zfs_commit_timeout_pct block commit timeout, increasing log latency more than desired. Handle that by introduction of zil_min_commit_timeout parameter, specifying minimal timeout value where additional delays to aggregate writes may be skipped. Also skip delays if the LWB is more than 7/8 full, that often happens if I/O sizes are constant and match one of LWB sizes. Both things are applied only if there were no already outstanding log blocks, that may indicate single-threaded workload, that by definition can not benefit from the commit delays. While there, add short time moving average to zl_last_lwb_latency to make it more stable. Tests of single-threaded 4KB writes to NVDIMM SLOG on FreeBSD show IOPS increase by 9% instead of expected 5%. For zfs_commit_timeout_pct of 1 there IOPS increase by 5.5% instead of expected 1%. Reviewed-by: Allan Jude <[email protected]> Reviewed-by: Brian Behlendorf <[email protected]> Reviewed-by: Prakash Surya <[email protected]> Signed-off-by: Alexander Motin <[email protected]> Sponsored by: iXsystems, Inc. Closes #14418
* Man: fix defaults for zfs_dirty_data_max_maxGeorge Melikov2023-01-171-1/+4
| | | | | | | | | | It was changed in e99932f7dec6efeb006e225e0bf0901c30345cac, but without docs update. Reviewed-by: Alexander Motin <[email protected]> Reviewed-by: Brian Behlendorf <[email protected]> Reviewed-by: Richard Yao <[email protected]> Signed-off-by: George Melikov <[email protected]> Closes #14400
* Turn default_bs and default_ibs into ZFS_MODULE_PARAMsMateusz Piotrowski2023-01-111-1/+7
| | | | | | | | | | | | | | | | | | | | | | | The default_bs and default_ibs tunables control the default block size and indirect block size. So far, default_bs and default_ibs were tunable only on FreeBSD, e.g., sysctl vfs.zfs.default_ibs Remove the FreeBSD-specific sysctl code and expose default_bs and default_ibs as tunables on both Linux and FreeBSD using ZFS_MODULE_PARAM. One of the use cases for changing the values of those tunables is to lower the indirect block size, which may improve performance of large directories (as discussed during the OpenZFS Leadership Meeting on 2022-08-16). Reviewed-by: Brian Behlendorf <[email protected]> Reviewed-by: Richard Yao <[email protected]> Signed-off-by: Mateusz Piotrowski <[email protected]> Sponsored-by: Wasabi Technology, Inc. Closes #14293
* Add tunable to allow changing micro ZAP's max sizeMateusz Piotrowski2023-01-101-1/+5
| | | | | | | | | | | | This change turns `MZAP_MAX_BLKSZ` into a `ZFS_MODULE_PARAM()` called `zap_micro_max_size`. As a result, we can experiment with different micro ZAP sizes to improve directory size scaling. Reviewed-by: Brian Behlendorf <[email protected]> Co-authored-by: Mateusz Piotrowski <[email protected]> Co-authored-by: Toomas Soome <[email protected]> Signed-off-by: Mateusz Piotrowski <[email protected]> Sponsored-by: Wasabi Technology, Inc. Closes #14292
* Hide b_freeze_* under ZFS_DEBUGAlexander Motin2023-01-051-1/+1
| | | | | | | | | | | This saves 40 bytes per full ARC header, reducing it on FreeBSD from 240 to 200 bytes on production bits. Reviewed-by: Ryan Moeller <[email protected]> Reviewed-by: Richard Yao <[email protected]> Reviewed-by: Brian Behlendorf <[email protected]> Reviewed-by: Matthew Ahrens <[email protected]> Signed-off-by: Alexander Motin <[email protected]> Closes #14315
* zfs.4: Correct the default for zfs_vdev_async_write_max_activeAllan Jude2022-11-281-1/+1
| | | | | | | Reviewed-by: Alexander Motin <[email protected]> Reviewed-by: Richard Yao <[email protected]> Reviewed-by: George Melikov <[email protected]> Signed-off-by: Allan Jude <[email protected]> Closes #14179
* Ubuntu 22.04 integration: mancheckszubersk2022-11-182-32/+55
| | | | | | | | | | | | | | Correct new mandoc errors. ``` STYLE: input text line longer than 80 bytes STYLE: no blank before trailing delimiter ``` Reviewed-by: Brian Behlendorf <[email protected]> Reviewed-by: Richard Yao <[email protected]> Reviewed-by: George Melikov <[email protected]> Signed-off-by: szubersk <[email protected]> Closes #14148
* Allow to control failfastMariusz Zaborski2022-11-101-2/+15
| | | | | | | | | | | | | | | | | | | | | Linux defaults to setting "failfast" on BIOs, so that the OS will not retry IOs that fail, and instead report the error to ZFS. In some cases, such as errors reported by the HBA driver, not the device itself, we would wish to retry rather than generating vdev errors in ZFS. This new property allows that. This introduces a per vdev option to disable the failfast option. This also introduces a global module parameter to define the failfast mask value. Reviewed-by: Brian Behlendorf <[email protected]> Co-authored-by: Allan Jude <[email protected]> Signed-off-by: Allan Jude <[email protected]> Signed-off-by: Mariusz Zaborski <[email protected]> Sponsored-by: Seagate Technology LLC Submitted-by: Klara, Inc. Closes #14056
* quota: disable quota check for ZVOLMariusz Zaborski2022-11-081-1/+5
| | | | | | | | | | | | | | | | | | | The quota for ZVOLs is set to the size of the volume. When the quota reaches the maximum, there isn't an excellent way to check if the new writers are overwriting the data or if they are inserting a new one. Because of that, when we reach the maximum quota, we wait till txg is flushed. This is causing a significant fluctuation in bandwidth. In the case of ZVOL, the quota is enforced by the volsize, so we can omit it. This commit adds a sysctl thats allow to control if the quota mechanism should be enforced or not. Reviewed-by: Brian Behlendorf <[email protected]> Signed-off-by: Mariusz Zaborski <[email protected]> Sponsored-by: Zededa Inc. Sponsored-by: Klara Inc. Closes #13838
* Expose zfs_vdev_open_timeout_ms as a tunableSerapheim Dimitropoulos2022-11-031-0/+7
| | | | | | | | | | | | | | | | | | | | | | Some of our customers have been occasionally hitting zfs import failures in Linux because udevd doesn't create the by-id symbolic links in time for zpool import to use them. The main issue is that the systemd-udev-settle.service that zfs-import-cache.service and other services depend on is racy. There is also an openzfs issue filed (see https://github.com/openzfs/zfs/issues/10891) outlining the problem and potential solutions. With the proper solutions being significant in terms of complexity and the priority of the issue being low for the time being, this patch exposes `zfs_vdev_open_timeout_ms` as a tunable so people that are experiencing this issue often can increase it as a workaround. Reviewed-by: Matthew Ahrens <[email protected]> Reviewed-by: Richard Yao <[email protected]> Reviewed-by: Alexander Motin <[email protected]> Reviewed-by: Don Brady <[email protected]> Reviewed-by: Brian Behlendorf <[email protected]> Signed-off-by: Serapheim Dimitropoulos <[email protected]> Closes #14133
* Cleanup: 64-bit kernel module parameters should use fixed width typesRichard Yao2022-10-131-58/+59
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Various module parameters such as `zfs_arc_max` were originally `uint64_t` on OpenSolaris/Illumos, but were changed to `unsigned long` for Linux compatibility because Linux's kernel default module parameter implementation did not support 64-bit types on 32-bit platforms. This caused problems when porting OpenZFS to Windows because its LLP64 memory model made `unsigned long` a 32-bit type on 64-bit, which created the undesireable situation that parameters that should accept 64-bit values could not on 64-bit Windows. Upon inspection, it turns out that the Linux kernel module parameter interface is extensible, such that we are allowed to define our own types. Rather than maintaining the original type change via hacks to to continue shrinking module parameters on 32-bit Linux, we implement support for 64-bit module parameters on Linux. After doing a review of all 64-bit kernel parameters (found via the man page and also proposed changes by Andrew Innes), the kernel module parameters fell into a few groups: Parameters that were originally 64-bit on Illumos: * dbuf_cache_max_bytes * dbuf_metadata_cache_max_bytes * l2arc_feed_min_ms * l2arc_feed_secs * l2arc_headroom * l2arc_headroom_boost * l2arc_write_boost * l2arc_write_max * metaslab_aliquot * metaslab_force_ganging * zfetch_array_rd_sz * zfs_arc_max * zfs_arc_meta_limit * zfs_arc_meta_min * zfs_arc_min * zfs_async_block_max_blocks * zfs_condense_max_obsolete_bytes * zfs_condense_min_mapping_bytes * zfs_deadman_checktime_ms * zfs_deadman_synctime_ms * zfs_initialize_chunk_size * zfs_initialize_value * zfs_lua_max_instrlimit * zfs_lua_max_memlimit * zil_slog_bulk Parameters that were originally 32-bit on Illumos: * zfs_per_txg_dirty_frees_percent Parameters that were originally `ssize_t` on Illumos: * zfs_immediate_write_sz Note that `ssize_t` is `int32_t` on 32-bit and `int64_t` on 64-bit. It has been upgraded to 64-bit. Parameters that were `long`/`unsigned long` because of Linux/FreeBSD influence: * l2arc_rebuild_blocks_min_l2size * zfs_key_max_salt_uses * zfs_max_log_walking * zfs_max_logsm_summary_length * zfs_metaslab_max_size_cache_sec * zfs_min_metaslabs_to_flush * zfs_multihost_interval * zfs_unflushed_log_block_max * zfs_unflushed_log_block_min * zfs_unflushed_log_block_pct * zfs_unflushed_max_mem_amt * zfs_unflushed_max_mem_ppm New parameters that do not exist in Illumos: * l2arc_trim_ahead * vdev_file_logical_ashift * vdev_file_physical_ashift * zfs_arc_dnode_limit * zfs_arc_dnode_limit_percent * zfs_arc_dnode_reduce_percent * zfs_arc_meta_limit_percent * zfs_arc_sys_free * zfs_deadman_ziotime_ms * zfs_delete_blocks * zfs_history_output_max * zfs_livelist_max_entries * zfs_max_async_dedup_frees * zfs_max_nvlist_src_size * zfs_rebuild_max_segment * zfs_rebuild_vdev_limit * zfs_unflushed_log_txg_max * zfs_vdev_max_auto_ashift * zfs_vdev_min_auto_ashift * zfs_vnops_read_chunk_size * zvol_max_discard_blocks Rather than clutter the lists with commentary, the module parameters that need comments are repeated below. A few parameters were defined in Linux/FreeBSD specific code, where the use of ulong/long is not an issue for portability, so we leave them alone: * zfs_delete_blocks * zfs_key_max_salt_uses * zvol_max_discard_blocks The documentation for a few parameters was found to be incorrect: * zfs_deadman_checktime_ms - incorrectly documented as int * zfs_delete_blocks - not documented as Linux only * zfs_history_output_max - incorrectly documented as int * zfs_vnops_read_chunk_size - incorrectly documented as long * zvol_max_discard_blocks - incorrectly documented as ulong The documentation for these has been fixed, alongside the changes to document the switch to fixed width types. In addition, several kernel module parameters were percentages or held ashift values, so being 64-bit never made sense for them. They have been downgraded to 32-bit: * vdev_file_logical_ashift * vdev_file_physical_ashift * zfs_arc_dnode_limit_percent * zfs_arc_dnode_reduce_percent * zfs_arc_meta_limit_percent * zfs_per_txg_dirty_frees_percent * zfs_unflushed_log_block_pct * zfs_vdev_max_auto_ashift * zfs_vdev_min_auto_ashift Of special note are `zfs_vdev_max_auto_ashift` and `zfs_vdev_min_auto_ashift`, which were already defined as `uint64_t`, and passed to the kernel as `ulong`. This is inherently buggy on big endian 32-bit Linux, since the values would not be written to the correct locations. 32-bit FreeBSD was unaffected because its sysctl code correctly treated this as a `uint64_t`. Lastly, a code comment suggests that `zfs_arc_sys_free` is Linux-specific, but there is nothing to indicate to me that it is Linux-specific. Nothing was done about that. Reviewed-by: Brian Behlendorf <[email protected]> Reviewed-by: Jorgen Lundman <[email protected]> Reviewed-by: Ryan Moeller <[email protected]> Reviewed-by: Alexander Motin <[email protected]> Original-patch-by: Andrew Innes <[email protected]> Original-patch-by: Jorgen Lundman <[email protected]> Signed-off-by: Richard Yao <[email protected]> Closes #13984 Closes #14004
* Bring per_txg_dirty_frees_percent back to 30Mateusz Guzik2022-09-271-1/+1
| | | | | | | | | | | | | | | | | | | | | The current value causes significant artificial slowdown during mass parallel file removal, which can be observed both on FreeBSD and Linux when running real workloads. Sample results from Linux doing make -j 96 clean after an allyesconfig modules build: before: 4.14s user 6.79s system 48% cpu 22.631 total after: 4.17s user 6.44s system 153% cpu 6.927 total FreeBSD results in the ticket. Reviewed-by: Alexander Motin <[email protected]> Reviewed-by: Brian Behlendorf <[email protected]> Reviewed-by: Richard Yao <[email protected]> Reviewed-by: George Melikov <[email protected]> Signed-off-by: Mateusz Guzik <[email protected]> Closes #13932 Closes #13938
* Cleanup: Specify unsignedness on things that should not be signedRichard Yao2022-09-271-105/+105
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In #13871, zfs_vdev_aggregation_limit_non_rotating and zfs_vdev_aggregation_limit being signed was pointed out as a possible reason not to eliminate an unnecessary MAX(unsigned, 0) since the unsigned value was assigned from them. There is no reason for these module parameters to be signed and upon inspection, it was found that there are a number of other module parameters that are signed, but should not be, so we make them unsigned. Making them unsigned made it clear that some other variables in the code should also be unsigned, so we also make those unsigned. This prevents users from setting negative values that could potentially cause bad behaviors. It also makes the code slightly easier to understand. Mostly module parameters that deal with timeouts, limits, bitshifts and percentages are made unsigned by this. Any that are boolean are left signed, since whether booleans should be considered signed or unsigned does not matter. Making zfs_arc_lotsfree_percent unsigned caused a `zfs_arc_lotsfree_percent >= 0` check to become redundant, so it was removed. Removing the check was also necessary to prevent a compiler error from -Werror=type-limits. Several end of line comments had to be moved to their own lines because replacing int with uint_t caused us to exceed the 80 character limit enforced by cstyle.pl. The following were kept signed because they are passed to taskq_create(), which expects signed values and modifying the OpenSolaris/Illumos DDI is out of scope of this patch: * metaslab_load_pct * zfs_sync_taskq_batch_pct * zfs_zil_clean_taskq_nthr_pct * zfs_zil_clean_taskq_minalloc * zfs_zil_clean_taskq_maxalloc * zfs_arc_prune_task_threads Also, negative values in those parameters was found to be harmless. The following were left signed because either negative values make sense, or more analysis was needed to determine whether negative values should be disallowed: * zfs_metaslab_switch_threshold * zfs_pd_bytes_max * zfs_livelist_min_percent_shared zfs_multihost_history was made static to be consistent with other parameters. A number of module parameters were marked as signed, but in reality referenced unsigned variables. upgrade_errlog_limit is one of the numerous examples. In the case of zfs_vdev_async_read_max_active, it was already uint32_t, but zdb had an extern int declaration for it. Interestingly, the documentation in zfs.4 was right for upgrade_errlog_limit despite the module parameter being wrongly marked, while the documentation for zfs_vdev_async_read_max_active (and friends) was wrong. It was also wrong for zstd_abort_size, which was unsigned, but was documented as signed. Also, the documentation in zfs.4 incorrectly described the following parameters as ulong when they were int: * zfs_arc_meta_adjust_restarts * zfs_override_estimate_recordsize They are now uint_t as of this patch and thus the man page has been updated to describe them as uint. dbuf_state_index was left alone since it does nothing and perhaps should be removed in another patch. If any module parameters were missed, they were not found by `grep -r 'ZFS_MODULE_PARAM' | grep ', INT'`. I did find a few that grep missed, but only because they were in files that had hits. This patch intentionally did not attempt to address whether some of these module parameters should be elevated to 64-bit parameters, because the length of a long on 32-bit is 32-bit. Lastly, it was pointed out during review that uint_t is a better match for these variables than uint32_t because FreeBSD kernel parameter definitions are designed for uint_t, whose bit width can change in future memory models. As a result, we change the existing parameters that are uint32_t to use uint_t. Reviewed-by: Alexander Motin <[email protected]> Reviewed-by: Brian Behlendorf <[email protected]> Reviewed-by: Neal Gompa <[email protected]> Signed-off-by: Richard Yao <[email protected]> Closes #13875
* Dynamically size dbuf hash mutex arrayBrian Behlendorf2022-09-221-0/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Incorrectly sizing the array of hash locks used to protect the dbuf hash table can lead to contention and reduce performance. We could unconditionally allocate a larger array for the locks but it's wasteful, particularly for a low-memory system. Instead, dynamically allocate the array of locks and scale it based on total system memory. Additionally, add a new `dbuf_mutex_cache_shift` module option which can be used to override the hash lock array size. This is disabled by default (dbuf_mutex_hash_shift=0) and can only be set at module load time. The minimum target array size is set to 8192, this matches the current constant value. Note that the count of the dbuf hash table and count of the mutex array were added to the /proc/spl/kstat/zfs/dbufstats kstat. Finally, this change removes the _KERNEL conditional checks. These were not required since for the user space build there is no difference between the kmem and vmem interfaces. Reviewed-by: Ryan Moeller <[email protected]> Reviewed-by: Richard Yao <[email protected]> Reviewed-by: Tony Hutter <[email protected]> Reviewed-by: Alexander Motin <[email protected]> Signed-off-by: Brian Behlendorf <[email protected]> Closes #13928
* Add zfs_blake3_impl to zfs.4Tino Reichardt2022-09-161-0/+14
| | | | | | | | | | | | The zfs module parameter zfs_blake3_impl got no manual page entry while adding BLAKE3 to OpenZFS. This commit adds the required notes about the parameter into zfs.4 Reviewed-by: Brian Behlendorf <[email protected]> Reviewed-by: Ryan Moeller <[email protected]> Co-authored-by: Ryan Moeller <[email protected]> Signed-off-by: Tino Reichardt <[email protected]> Closes #13725
* Add zfs_btree_verify_intensity kernel module parameterRichard Yao2022-09-151-0/+16
| | | | | | | | | | I see a few issues in the issue tracker that might be aided by being able to turn this on. We have no module parameter for it, so I would like to add one. Reviewed-by: Alexander Motin <[email protected]> Reviewed-by: Brian Behlendorf <[email protected]> Signed-off-by: Richard Yao <[email protected]> Closes #13874
* Improve too large physical ashift handlingAlexander Motin2022-09-081-1/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When iterating through children physical ashifts for vdev, prefer ones above the maximum logical ashift, that we can actually use, but within the administrator defined maximum. When selecting top-level vdev ashift, do not set it to the defined maximum in case physical ashift is even higher, but just ignore one. Using the maximum does not prevent misaligned writes, but reduces space efficiency. Since ZFS tries to write data sequentially and aggregates the writes, in many cases large misanigned writes may be not as bad as the space penalty otherwise. Allow internal physical ashifts for vdevs higher than SHIFT_MAX. May be one day allocator or aggregation could benefit from that. Reduce zfs_vdev_max_auto_ashift default from 16 (64KB) to 14 (16KB), so that ZFS may still use bigger ashifts up to SHIFT_MAX (64KB), but only if it really has to or explicitly told to, but not as an "optimization". There are some read-intensive NVMe SSDs that report Preferred Write Alignment of 64KB, and attempt to build RAIDZ2 of those leads to a space inefficiency that can't be justified. Instead these changes make ZFS fall back to logical ashift of 12 (4KB) by default and only warn user that it may be suboptimal for performance. Reviewed-by: Brian Behlendorf <[email protected]> Reviewed-by: Ryan Moeller <[email protected]> Signed-off-by: Alexander Motin <[email protected]> Sponsored by: iXsystems, Inc. Closes #13798
* Implement a new type of zfs receive: corrective receive (-c)Alek P2022-07-281-0/+11
| | | | | | | | | | | | | | This type of recv is used to heal corrupted data when a replica of the data already exists (in the form of a send file for example). With the provided send stream, corrective receive will read from disk blocks described by the WRITE records. When any of the reads come back with ECKSUM we use the data from the corresponding WRITE record to rewrite the corrupted block. Reviewed-by: Paul Dagnelie <[email protected]> Reviewed-by: Brian Behlendorf <[email protected]> Reviewed-by: Paul Zuchowski <[email protected]> Signed-off-by: Alek Pinchuk <[email protected]> Closes #9372
* Replace dead opensolaris.org license linkTino Reichardt2022-07-112-2/+2
| | | | | | | | | The commit replaces all findings of the link: http://www.opensolaris.org/os/licensing with this one: https://opensource.org/licenses/CDDL-1.0 Reviewed-by: Brian Behlendorf <[email protected]> Signed-off-by: Tino Reichardt <[email protected]> Closes #13619
* zvol: Support blk-mq for better performanceTony Hutter2022-06-091-2/+67
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add support for the kernel's block multiqueue (blk-mq) interface in the zvol block driver. blk-mq creates multiple request queues on different CPUs rather than having a single request queue. This can improve zvol performance with multithreaded reads/writes. This implementation uses the blk-mq interfaces on 4.13 or newer kernels. Building against older kernels will fall back to the older BIO interfaces. Note that you must set the `zvol_use_blk_mq` module param to enable the blk-mq API. It is disabled by default. In addition, this commit lets the zvol blk-mq layer process whole `struct request` IOs at a time, rather than breaking them down into their individual BIOs. This reduces dbuf lock contention and overhead versus the legacy zvol submit_bio() codepath. sequential dd to one zvol, 8k volblocksize, no O_DIRECT: legacy submit_bio() 292MB/s write 453MB/s read this commit 453MB/s write 885MB/s read It also introduces a new `zvol_blk_mq_chunks_per_thread` module parameter. This parameter represents how many volblocksize'd chunks to process per each zvol thread. It can be used to tune your zvols for better read vs write performance (higher values favor write, lower favor read). Reviewed-by: Brian Behlendorf <[email protected]> Reviewed-by: Ahelenia Ziemiańska <[email protected]> Reviewed-by: Tony Nguyen <[email protected]> Signed-off-by: Tony Hutter <[email protected]> Closes #13148 Issue #12483
* Corrected parameters for zstd early abortRich Ercolani2022-05-311-2/+2
| | | | | | | That'll teach me to try and recall them from the definition. Reviewed-by: Brian Behlendorf <[email protected]> Signed-off-by: Rich Ercolani <[email protected]> Closes #13519
* More speculative prefetcher improvementsAlexander Motin2022-05-251-3/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | - Make prefetch distance adaptive: up to 4MB prefetch doubles for every, hit same as before, but after that it grows by 1/8 every time the prefetch read does not complete in time to satisfy the demand. My tests show that 4MB is sufficient for wide NVMe pool to saturate single reader thread at 2.5GB/s, while new 64MB maximum allows the same thread to reach 1.5GB/s on wide HDD pool. Further distance increase may increase speed even more, but less dramatic and with higher latency. - Allow early reuse of inactive prefetch streams: streams that never saw hits can be reused immediately if there is a demand, while others can be reused after 1s of inactivity, starting with the oldest. After 2s of inactivity streams are deleted to free resources same as before. This allows by several times increase strided read performance on HDD pool in presence of simultaneous random reads, previously filling the zfetch_max_streams limit for seconds and so blocking most of prefetch. - Always issue intermediate indirect block reads with SYNC priority. Each of those reads if delayed for longer may delay up to 1024 other block prefetches, that may be not good for wide pools. Reviewed-by: Allan Jude <[email protected]> Reviewed-by: Brian Behlendorf <[email protected]> Signed-off-by: Alexander Motin <[email protected]> Sponsored-By: iXsystems, Inc. Closes #13452
* Refactor Log Size LimitAlexander Motin2022-05-241-4/+3
| | | | | | | | | | | | | | | Original Log Size Limit implementation blocked all writes in case of limit reached until the TXG is committed and the log is freed. It caused huge delays and following speed spikes in application writes. This implementation instead smoothly throttles writes, using exactly the same mechanism as used for dirty data. Reviewed-by: Brian Behlendorf <[email protected]> Reviewed-by: jxdking <[email protected]> Signed-off-by: Alexander Motin <[email protected]> Sponsored-By: iXsystems, Inc. Issue #12284 Closes #13476
* Tiered early abort, zstd editionRich Ercolani2022-05-241-0/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | It turns out that "do LZ4 and zstd-1 both fail" is a great heuristic for "don't even bother trying higher zstd tiers". By way of illustration: $ cat /incompress | mbuffer | zfs recv -o compression=zstd-12 evenfaster/lowcomp_1M_zstd12_normal summary: 39.8 GiByte in 3min 40.2sec - average of 185 MiB/s $ echo 3 | sudo tee /sys/module/zzstd/parameters/zstd_lz4_pass 3 $ cat /incompress | mbuffer -m 4G | zfs recv -o compression=zstd-12 evenfaster/lowcomp_1M_zstd12_patched summary: 39.8 GiByte in 48.6sec - average of 839 MiB/s $ sudo zfs list -p -o name,used,lused,ratio evenfaster/lowcomp_1M_zstd12_normal evenfaster/lowcomp_1M_zstd12_patched NAME USED LUSED RATIO evenfaster/lowcomp_1M_zstd12_normal 39549931520 42721221632 1.08 evenfaster/lowcomp_1M_zstd12_patched 39626399744 42721217536 1.07 $ python3 -c "print(39626399744 - 39549931520)" 76468224 $ I'll take 76 MB out of 42 GB for > 4x speedup. Reviewed-by: Allan Jude <[email protected]> Reviewed-by: Brian Behlendorf <[email protected]> Reviewed-by: George Melikov <[email protected]> Reviewed-by: Kjeld Schouten <[email protected]> Reviewed-by: Ahelenia Ziemiańska <[email protected]> Signed-off-by: Rich Ercolani <[email protected]> Closes #13244
* Fix incorrect use of unit prefix names in man pagesWHR2022-05-041-86/+86
| | | | | | | | Reviewed-by: George Melikov <[email protected]> Reviewed-by: Brian Behlendorf <[email protected]> Reviewed-by: Damian Szuberski <[email protected]> Signed-off-by: WHR <[email protected]> Closes #13363
* Improve mg_aliquot mathAlexander Motin2022-05-041-3/+3
| | | | | | | | | | | | | | | When calculating mg_aliquot alike to #12046 use number of unique data disks in the vdev, not the total number of children vdev. Increase default value of the tunable from 512KB to 1MB to compensate. Before this change each disk in striped pool was getting 512KB of sequential data, in 2-wide mirror -- 1MB, in 3-wide RAIDZ1 -- 768KB. After this change in all the cases each disk should get 1MB. Reviewed-by: Brian Behlendorf <[email protected]> Reviewed-by: Ryan Moeller <[email protected]> Signed-off-by: Alexander Motin <[email protected]> Sponsored-By: iXsystems, Inc. Closes #13388
* Default zfs_max_recordsize to 16MRich Ercolani2022-04-281-3/+3
| | | | | | | | | | | | | | | | | | | | Increase the default allowed maximum recordsize from 1M to 16M. As described in the zfs(4) man page, there are significant costs which need to be considered before using very large blocks. However, there are scenarios where they make good sense and it should no longer be necessary to artificially restrict their use behind a module option. Note that for 32-bit platforms we continue to leave this restriction in place due to the limited virtual address space available (256-512MB). On these systems only a handful of blocks could be cached at any one time severely impacting performance and potentially stability. Reviewed-by: Brian Behlendorf <[email protected]> Reviewed-by: Alexander Motin <[email protected]> Signed-off-by: Rich Ercolani <[email protected]> Closes #12830 Closes #13302
* Improve log spacemap load timeAlexander Motin2022-04-261-4/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Previous flushing algorithm limited only total number of log blocks to the minimum of 256K and 4x number of metaslabs in the pool. As result, system with 1500 disks with 1000 metaslabs each, touching several new metaslabs each TXG could grow spacemap log to huge size without much benefits. We've observed one of such systems importing pool for about 45 minutes. This patch improves the situation from five sides: - By limiting maximum period for each metaslab to be flushed to 1000 TXGs, that effectively limits maximum number of per-TXG spacemap logs to load to the same number. - By making flushing more smooth via accounting number of metaslabs that were touched after the last flush and actually need another flush, not just ms_unflushed_txg bump. - By applying zfs_unflushed_log_block_pct to the number of metaslabs that were touched after the last flush, not all metaslabs in the pool. - By aggressively prefetching per-TXG spacemap logs up to 16 TXGs in advance, making log spacemap load process for wide HDD pool CPU-bound, accelerating it by many times. - By reducing zfs_unflushed_log_block_max from 256K to 128K, reducing single-threaded by nature log processing time from ~10 to ~5 minutes. As further optimization we could skip bumping ms_unflushed_txg for metaslabs not touched since the last flush, but that would be an incompatible change, requiring new pool feature. Reviewed-by: Matthew Ahrens <[email protected]> Reviewed-by: Brian Behlendorf <[email protected]> Signed-off-by: Alexander Motin <[email protected]> Sponsored-By: iXsystems, Inc. Closes #12789
* Improve zpool status output, list all affected datasetsGeorge Amanakis2022-04-251-0/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, determining which datasets are affected by corruption is a manual process. The primary difficulty in reporting the list of affected snapshots is that since the error was initially found, the snapshot where the error originally occurred in, may have been deleted. To solve this issue, we add the ID of the head dataset of the original snapshot which the error was detected in, to the stored error report. Then any time a filesystem is deleted, the errors associated with it are deleted as well. Any time a clone promote occurs, we modify reports associated with the original head to refer to the new head. The stored error reports are identified by this head ID, the birth time of the block which the error occurred in, as well as some information about the error itself are also stored. Once this information is stored, we can find the set of datasets affected by an error by walking back the list of snapshots in the given head until we find one with the appropriate birth txg, and then traverse through the snapshots of the clone family, terminating a branch if the block was replaced in a given snapshot. Then we report this information back to libzfs, and to the zpool status command, where it is displayed as follows: pool: test state: ONLINE status: One or more devices has experienced an error resulting in data corruption. Applications may be affected. action: Restore the file in question if possible. Otherwise restore the entire pool from backup. see: https://openzfs.github.io/openzfs-docs/msg/ZFS-8000-8A scan: scrub repaired 0B in 00:00:00 with 800 errors on Fri Dec 3 08:27:57 2021 config: NAME STATE READ WRITE CKSUM test ONLINE 0 0 0 sdb ONLINE 0 0 1.58K errors: Permanent errors have been detected in the following files: test@1:/test.0.0 /test/test.0.0 /test/1clone/test.0.0 A new feature flag is introduced to mark the presence of this change, as well as promotion and backwards compatibility logic. This is an updated version of #9175. Rebase required fixing the tests, updating the ABI of libzfs, updating the man pages, fixing bugs, fixing the error returns, and updating the old on-disk error logs to the new format when activating the feature. Reviewed-by: Matthew Ahrens <[email protected]> Reviewed-by: Brian Behlendorf <[email protected]> Reviewed-by: Mark Maybee <[email protected]> Reviewed-by: Tony Hutter <[email protected]> Co-authored-by: TulsiJain <[email protected]> Signed-off-by: George Amanakis <[email protected]> Closes #9175 Closes #12812
* log xattr=sa create/remove/update to ZILJitendra Patidar2022-02-221-0/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As such, there are no specific synchronous semantics defined for the xattrs. But for xattr=on, it does log to ZIL and zil_commit() is done, if sync=always is set on dataset. This provides sync semantics for xattr=on with sync=always set on dataset. For the xattr=sa implementation, it doesn't log to ZIL, so, even with sync=always, xattrs are not guaranteed to be synced before xattr call returns to caller. So, xattr can be lost if system crash happens, before txg carrying xattr transaction is synced. This change adds xattr=sa logging to ZIL on xattr create/remove/update and xattrs are synced to ZIL (zil_commit() done) for sync=always. This makes xattr=sa behavior similar to xattr=on. Implementation notes: The actual logging is fairly straight-forward and does not warrant additional explanation. However, it has been 14 years since we last added new TX types to the ZIL [1], hence this is the first time we do it after the introduction of zpool features. Therefore, here is an overview of the feature activation and deactivation workflow: 1. The feature must be enabled. Otherwise, we don't log the new record type. This ensures compatibility with older software. 2. The feature is activated per-dataset, since the ZIL is per-dataset. 3. If the feature is enabled and dataset is not for zvol, any append to the ZIL chain will activate the feature for the dataset. Likewise for starting a new ZIL chain. 4. A dataset that doesn't have a ZIL chain has the feature deactivated. We ensure (3) by activating on the first zil_commit() after the feature was enabled. Since activating the features requires waiting for txg sync, the first zil_commit() after enabling the feature will be slower than usual. The downside is that this is really a conservative approximation: even if we never append a 'TX_SETSAXATTR' to the ZIL chain, we pay the penalty for feature activation. The upside is that the user is in control of when we pay the penalty, i.e., upon enabling the feature. We ensure (4) by hooking into zil_sync(), where ZIL destroy actually happens. One more piece on feature activation, since it's spread across multiple functions: zil_commit() zil_process_commit_list() if lwb == NULL // first zil_commit since zil_open zil_create() if no log block pointer in ZIL header: if feature enabled and not active: // CASE 1 enable, COALESCE txg wait with dmu_tx that allocated the log block else // log block was allocated earlier than this zil_open if feature enabled and not active: // CASE 2 enable, EXPLICIT txg wait else // already have an in-DRAM LWB if feature enabled and not active: // this happens when we enable the feature after zil_create // CASE 3 enable, EXPLICIT txg wait [1] https://github.com/illumos/illumos-gate/commit/da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0 Reviewed-by: Matthew Ahrens <[email protected]> Reviewed-by: Christian Schwarz <[email protected]> Reviewed-by: Ahelenia Ziemiańska <[email protected]> Reviewed-by: Ryan Moeller <[email protected]> Reviewed-by: Brian Behlendorf <[email protected]> Signed-off-by: Jitendra Patidar <[email protected]> Closes #8768 Closes #9078
* man: full stop at EOLнаб2022-02-221-3/+4
| | | | | | Reviewed by: Brian Behlendorf <[email protected]> Signed-off-by: Ahelenia Ziemiańska <[email protected]> Closes #13116
* man: IO -> I/O; I/Os -> I/O operations againнаб2022-02-221-6/+6
| | | | | | Reviewed by: Brian Behlendorf <[email protected]> Signed-off-by: Ahelenia Ziemiańska <[email protected]> Closes #13116
* Cross-platform xattr user namespace compatibilityRyan Moeller2022-02-151-0/+24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | ZFS on Linux originally implemented xattr namespaces in a way that is incompatible with other operating systems. On illumos, xattrs do not have namespaces. Every xattr name is visible. FreeBSD has two universally defined namespaces: EXTATTR_NAMESPACE_USER and EXTATTR_NAMESPACE_SYSTEM. The system namespace is used for protected FreeBSD-specific attributes such as MAC labels and pnfs state. These attributes have the namespace string "freebsd:system:" prefixed to the name in the encoding scheme used by ZFS. The user namespace is used for general purpose user attributes and obeys normal access control mechanisms. These attributes have no namespace string prefixed, so xattrs written on illumos are accessible in the user namespace on FreeBSD, and xattrs written to the user namespace on FreeBSD are accessible by the same name on illumos. Linux has several xattr namespaces. On Linux, ZFS encodes the namespace in the xattr name for every namespace, including the user namespace. As a consequence, an xattr in the user namespace with the name "foo" is stored by ZFS with the name "user.foo" and therefore appears on FreeBSD and illumos to have the name "user.foo" rather than "foo". Conversely, none of the xattrs written on FreeBSD or illumos are accessible on Linux unless the name happens to be prefixed with one of the Linux xattr namespaces, in which case the namespace is stripped from the name. This makes xattrs entirely incompatible between Linux and other platforms. We want to make the encoding of user namespace xattrs compatible across platforms. A critical requirement of this compatibility is for xattrs from existing pools from FreeBSD and illumos to be accessible by the same names in the user namespace on Linux. It is also necessary that existing pools with xattrs written by Linux retain access to those xattrs by the same names on Linux. Making user namespace xattrs from Linux accessible by the correct names on other platforms is important. The handling of other namespaces is not required to be consistent. Add a fallback mechanism for listing and getting xattrs to treat xattrs as being in the user namespace if they do not match a known prefix. Do not allow setting or getting xattrs with a name that is prefixed with one of the namespace names used by ZFS on supported platforms. Allow choosing between legacy illumos and FreeBSD compatibility and legacy Linux compatibility with a new tunable. This facilitates replication and migration of pools between hosts with different compatibility needs. The tunable controls whether or not to prefix the namespace to the name. If the xattr is already present with the alternate prefix, remove it so only the new version persists. By default the platform's existing convention is used. Reviewed-by: Christian Schwarz <[email protected]> Reviewed-by: Ahelenia Ziemiańska <[email protected]> Reviewed-by: Alexander Motin <[email protected]> Reviewed-by: Brian Behlendorf <[email protected]> Signed-off-by: Ryan Moeller <[email protected]> Closes #11919
* man: zfs.4: miscellaneous cleanupнаб2022-01-131-21/+20
| | | | | Reviewed-by: Brian Behlendorf <[email protected]> Signed-off-by: Ahelenia Ziemiańska <[email protected]> Closes #12941
* man: spelingchrisrd2022-01-061-3/+3
| | | | | | | | | Fix spelling. Reviewed-by: Rich Ercolani <[email protected]> Reviewed-by: Matthew Ahrens <[email protected]> Reviewed-by: Brian Behlendorf <[email protected]> Signed-off-by: Chris Dunlop <[email protected]> Closes #12911
* Reduce number of arc_prune threadsAlexander Motin2021-12-221-0/+7
| | | | | | | | | | | | | | | | On FreeBSD vnode reclamation is single-threaded, protected by single global lock. Linux seems to be able to use a thread per mount point, but at this time it creates more harm than good. Reduce number of threads to 1, adding tunable in case somebody wants to try more. Reviewed-by: Ryan Moeller <[email protected]> Reviewed-by: Brian Behlendorf <[email protected]> Reviewed-by: Chris Dunlop <[email protected]> Reviewed-by: Ahelenia Ziemiańska <[email protected]> Signed-off-by: Alexander Motin <[email protected]> Closes #12896 Issue #9966
* Default to zfs_dmu_offset_next_sync=1Brian Behlendorf2021-11-301-4/+4
| | | | | | | | | | | | Strict hole reporting was previously disabled by default as a performance optimization. However, this has lead to confusion over the expected behavior and a variety of workarounds being adopted by consumers of ZFS. Change the default behavior to always report holes and force the TXG sync. Reviewed-by: Matthew Ahrens <[email protected]> Reviewed-by: Tony Hutter <[email protected]> Signed-off-by: Brian Behlendorf <[email protected]> Closes #12746
* Replace wrong occurrences of `affect` by `effect` in the man pagesmaxz2021-11-301-1/+1
| | | | | | Reviewed-by: Brian Behlendorf <[email protected]> Reviewed-by: George Amanakis <[email protected]> Signed-off-by: Max Zettlmeißl <[email protected]> Closes #12784
* Introduce a tunable to exclude special class buffers from L2ARCGeorge Amanakis2021-11-111-0/+5
| | | | | | | | | | | Special allocation class or dedup vdevs may have roughly the same performance as L2ARC vdevs. Introduce a new tunable to exclude those buffers from being cacheable on L2ARC. Reviewed-by: Don Brady <[email protected]> Reviewed-by: Brian Behlendorf <[email protected]> Signed-off-by: George Amanakis <[email protected]> Closes #11761 Closes #12285
* Fix lseek(SEEK_DATA/SEEK_HOLE) mmap consistencyBrian Behlendorf2021-11-071-1/+1
| | | | | | | | | | | | | | | | | | | | | | | When using lseek(2) to report data/holes memory mapped regions of the file were ignored. This could result in incorrect results. To handle this zfs_holey_common() was updated to asynchronously writeback any dirty mmap(2) regions prior to reporting holes. Additionally, while not strictly required, the dn_struct_rwlock is now held over the dirty check to prevent the dnode structure from changing. This ensures that a clean dnode can't be dirtied before the data/hole is located. The range lock is now also taken to ensure the call cannot race with zfs_write(). Furthermore, the code was refactored to provide a dnode_is_dirty() helper function which checks the dnode for any dirty records to determine its dirtiness. Reviewed-by: Matthew Ahrens <[email protected]> Reviewed-by: Tony Hutter <[email protected]> Reviewed-by: Rich Ercolani <[email protected]> Signed-off-by: Brian Behlendorf <[email protected]> Issue #11900 Closes #12724
* zfs.4: Fix typo s/compatiblity/compatibility/Gordon Bergling2021-08-171-1/+1
| | | | | | | Reviewed-by: George Melikov <[email protected]> Reviewed-by: Ryan Moeller <[email protected]> Reviewed-by: Tony Nguyen <[email protected]> Signed-off-by: Gordon Bergling <[email protected]> Closes #12464
* Add Module Parameter Regarding Log Size LimitKevin Jin2021-07-201-0/+12
| | | | | | | | | | | | | | * Add Module Parameters Regarding Log Size Limit zfs_wrlog_data_max The upper limit of TX_WRITE log data. Once it is reached, write operation is blocked, until log data is cleared out after txg sync. It only counts TX_WRITE log with WR_COPIED or WR_NEED_COPY. Reviewed-by: Prakash Surya <[email protected]> Reviewed-by: Brian Behlendorf <[email protected]> Signed-off-by: jxdking <[email protected]> Closes #12284
* Fix ARC ghost states eviction accountingAlexander Motin2021-07-131-11/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | arc_evict_hdr() returns number of evicted bytes in scope of specific state. For ghost states it does not mean the amount of really freed memory, but the logical buffer size. It is correct for the eviction process, but not for waking up threads waiting for ARC size reduction, as added in "Revise ARC shrinker algorithm" commit, causing premature wakeups while ARC is still overflowed, allowing even bigger overflow, plus processing overhead when next allocation will also get blocked, probably also for too short time. To fix that make arc_evict_hdr() also return the amount of really freed memory, which for the ghost states is only the header, and use it to update arc_evict_count instead. Originally I was thinking to not return it at all, since arc_get_data_impl() does not account for the headers, but decided that some slow allocation progress is better than long waits, reaching on my tests up to 100ms. To reduce negative latency effects of long time periods when reclaim thread can free little real memory, start reclamation process earlier, before we actually reached the overflow threshold, when we have to throttle new allocations. We can also do it without taking global arc_evict_lock, reducing the contention. Reviewed-by: George Wilson <[email protected]> Reviewed-by: Allan Jude <[email protected]> Reviewed-by: Ryan Moeller <[email protected]> Signed-off-by: Alexander Motin <[email protected]> Sponsored-By: iXsystems, Inc. Closes #12279