diff options
| author | Brian Behlendorf <[email protected]> | 2015-08-18 13:51:20 -0700 |
|---|---|---|
| committer | Brian Behlendorf <[email protected]> | 2015-09-09 14:38:29 -0700 |
| commit | 9965059ab9991a5fc7df9a489021e73880b3bcc0 (patch) | |
| tree | 0770e9f65b22908acd9e22f925fdd393e8fb312e /man/man5/zfs-module-parameters.5 | |
| parent | 8198d18ca7e05ec30139e10d658a8b06c0ec4c55 (diff) | |
Prefetch start and end of volumes
When adding a zvol to the system prefetch zvol_prefetch_bytes from the
start and end of the volume. Prefetching these regions of the volume is
desirable because they are likely to be accessed immediately by blkid(8),
the kernel scanning for a partition table, or another task which probes
the devices.
Signed-off-by: Richard Yao <[email protected]>
Signed-off-by: Brian Behlendorf <[email protected]>
Issue #3659
Diffstat (limited to 'man/man5/zfs-module-parameters.5')
| -rw-r--r-- | man/man5/zfs-module-parameters.5 | 15 |
1 files changed, 15 insertions, 0 deletions
diff --git a/man/man5/zfs-module-parameters.5 b/man/man5/zfs-module-parameters.5 index 6d4a8c304..015ab0186 100644 --- a/man/man5/zfs-module-parameters.5 +++ b/man/man5/zfs-module-parameters.5 @@ -1631,6 +1631,21 @@ Max number of blocks to discard at once Default value: \fB16,384\fR. .RE +.sp +.ne 2 +.na +\fBzvol_prefetch_bytes\fR (uint) +.ad +.RS 12n +When adding a zvol to the system prefetch \fBzvol_prefetch_bytes\fR +from the start and end of the volume. Prefetching these regions +of the volume is desirable because they are likely to be accessed +immediately by \fBblkid(8)\fR or by the kernel scanning for a partition +table. +.sp +Default value: \fB131,072\fR. +.RE + .SH ZFS I/O SCHEDULER ZFS issues I/O operations to leaf vdevs to satisfy and complete I/Os. The I/O scheduler determines when and in what order those operations are |