OpenZFS 9076 - Adjust perf test concurrency settings

ZFS Performance test concurrency should be lowered for better latency

Work by Stephen Blinick.

Nightly performance runs typically consist of two levels of concurrency;
and both are fairly high.

Since the IO runs are to a ZFS filesystem, within a zpool, which is
based on some variable number of vdev's, the amount of IO driven to each
device is variable. Additionally, different device types (HDD vs SSD,
etc) can generally handle a different amount of concurrent IO before
saturating.

Nevertheless, in practice, it appears that most tests are well past the
concurrency saturation point and therefore both perform with the same
throughput, the maximum of the device. Because the queuedepth to the
device(s) is so high however, the latency is much higher than the best
possible at that throughput, and increases linearly with the increase in
concurrency.

This means that changes in code that impact latency during normal
operation (before saturation) may not be apparent when a large component
of the measured latency is from the IO sitting in a queue to be
serviced. Therefore, changing the concurrency settings is recommended

Authored by: Stephen Blinick <[email protected]>
Reviewed-by: George Melikov <[email protected]>
Reviewed-by: Giuseppe Di Natale <[email protected]>
Reviewed-by: Brian Behlendorf <[email protected]>
Reviewed by: Dan Kimmel <[email protected]>
Reviewed by: John Wren Kennedy <[email protected]>
Ported-by: John Wren Kennedy <[email protected]>

OpenZFS-issue: https://www.illumos.org/issues/9076
OpenZFS-commit: https://github.com/openzfs/openzfs/pull/562
Upstream bug: DLPX-45477
Closes #7302

5 files changed, 55 insertions, 10 deletions

diff --git a/tests/zfs-tests/tests/perf/regression/random_reads.ksh b/tests/zfs-tests/tests/perf/regression/random_reads.ksh
index 8ec8cd67a..5e91fe0a7 100755
--- a/tests/zfs-tests/tests/perf/regression/random_reads.ksh
+++ b/tests/zfs-tests/tests/perf/regression/random_reads.ksh
@@ -25,6 +25,15 @@
 # for all fio runs. The ARC is cleared with `zinject -a` prior to each run
 # so reads will go to disk.
 #
+# Thread/Concurrency settings:
+#    PERF_NTHREADS defines the number of files created in the test filesystem,
+#    as well as the number of threads that will simultaneously drive IO to
+#    those files.  The settings chosen are from measurements in the
+#    PerfAutoESX/ZFSPerfESX Environments, selected at concurrency levels that
+#    are at peak throughput but lowest latency.  Higher concurrency introduces
+#    queue time latency and would reduce the impact of code-induced performance
+#    regressions.
+#
 
 . $STF_SUITE/include/libtest.shlib
 . $STF_SUITE/tests/perf/perf.shlib
@@ -54,13 +63,13 @@ export TOTAL_SIZE=$(($(get_prop avail $TESTFS) * 3 / 2))
 if [[ -n $PERF_REGRESSION_WEEKLY ]]; then
 	export PERF_RUNTIME=${PERF_RUNTIME:-$PERF_RUNTIME_WEEKLY}
 	export PERF_RUNTYPE=${PERF_RUNTYPE:-'weekly'}
-	export PERF_NTHREADS=${PERF_NTHREADS:-'8 16 64'}
+	export PERF_NTHREADS=${PERF_NTHREADS:-'8 16 32 64'}
 	export PERF_SYNC_TYPES=${PERF_SYNC_TYPES:-'1'}
 	export PERF_IOSIZES=${PERF_IOSIZES:-'8k'}
 elif [[ -n $PERF_REGRESSION_NIGHTLY ]]; then
 	export PERF_RUNTIME=${PERF_RUNTIME:-$PERF_RUNTIME_NIGHTLY}
 	export PERF_RUNTYPE=${PERF_RUNTYPE:-'nightly'}
-	export PERF_NTHREADS=${PERF_NTHREADS:-'64 128'}
+	export PERF_NTHREADS=${PERF_NTHREADS:-'16 32'}
 	export PERF_SYNC_TYPES=${PERF_SYNC_TYPES:-'1'}
 	export PERF_IOSIZES=${PERF_IOSIZES:-'8k'}
 fi
diff --git a/tests/zfs-tests/tests/perf/regression/random_readwrite.ksh b/tests/zfs-tests/tests/perf/regression/random_readwrite.ksh
index cf12c9b09..446a440ec 100755
--- a/tests/zfs-tests/tests/perf/regression/random_readwrite.ksh
+++ b/tests/zfs-tests/tests/perf/regression/random_readwrite.ksh
@@ -25,6 +25,15 @@
 # and used for all fio runs. The ARC is cleared with `zinject -a` prior to
 # each run so reads will go to disk.
 #
+# Thread/Concurrency settings:
+#    PERF_NTHREADS defines the number of files created in the test filesystem,
+#    as well as the number of threads that will simultaneously drive IO to
+#    those files.  The settings chosen are from measurements in the
+#    PerfAutoESX/ZFSPerfESX Environments, selected at concurrency levels that
+#    are at peak throughput but lowest latency.  Higher concurrency introduces
+#    queue time latency and would reduce the impact of code-induced performance
+#    regressions.
+#
 
 . $STF_SUITE/include/libtest.shlib
 . $STF_SUITE/tests/perf/perf.shlib
@@ -54,13 +63,13 @@ export TOTAL_SIZE=$(($(get_prop avail $TESTFS) * 3 / 2))
 if [[ -n $PERF_REGRESSION_WEEKLY ]]; then
 	export PERF_RUNTIME=${PERF_RUNTIME:-$PERF_RUNTIME_WEEKLY}
 	export PERF_RUNTYPE=${PERF_RUNTYPE:-'weekly'}
-	export PERF_NTHREADS=${PERF_NTHREADS:-'8 16 64'}
+	export PERF_NTHREADS=${PERF_NTHREADS:-'4 8 16 64'}
 	export PERF_SYNC_TYPES=${PERF_SYNC_TYPES:-'0 1'}
 	export PERF_IOSIZES=''		# bssplit used instead
 elif [[ -n $PERF_REGRESSION_NIGHTLY ]]; then
 	export PERF_RUNTIME=${PERF_RUNTIME:-$PERF_RUNTIME_NIGHTLY}
 	export PERF_RUNTYPE=${PERF_RUNTYPE:-'nightly'}
-	export PERF_NTHREADS=${PERF_NTHREADS:-'64 128'}
+	export PERF_NTHREADS=${PERF_NTHREADS:-'32 64'}
 	export PERF_SYNC_TYPES=${PERF_SYNC_TYPES:-'1'}
 	export PERF_IOSIZES=''		# bssplit used instead
 fi
diff --git a/tests/zfs-tests/tests/perf/regression/random_writes.ksh b/tests/zfs-tests/tests/perf/regression/random_writes.ksh
index 8db5fbd32..e724aefe2 100755
--- a/tests/zfs-tests/tests/perf/regression/random_writes.ksh
+++ b/tests/zfs-tests/tests/perf/regression/random_writes.ksh
@@ -24,6 +24,15 @@
 # Prior to each fio run the dataset is recreated, and fio writes new files
 # into an otherwise empty pool.
 #
+# Thread/Concurrency settings:
+#    PERF_NTHREADS defines the number of files created in the test filesystem,
+#    as well as the number of threads that will simultaneously drive IO to
+#    those files.  The settings chosen are from measurements in the
+#    PerfAutoESX/ZFSPerfESX Environments, selected at concurrency levels that
+#    are at peak throughput but lowest latency.  Higher concurrency introduces
+#    queue time latency and would reduce the impact of code-induced performance
+#    regressions.
+#
 
 . $STF_SUITE/include/libtest.shlib
 . $STF_SUITE/tests/perf/perf.shlib
@@ -53,13 +62,13 @@ export TOTAL_SIZE=$(($(get_prop avail $TESTFS) * 3 / 2))
 if [[ -n $PERF_REGRESSION_WEEKLY ]]; then
 	export PERF_RUNTIME=${PERF_RUNTIME:-$PERF_RUNTIME_WEEKLY}
 	export PERF_RUNTYPE=${PERF_RUNTYPE:-'weekly'}
-	export PERF_NTHREADS=${PERF_NTHREADS:-'8 16 64'}
+	export PERF_NTHREADS=${PERF_NTHREADS:-'1 4 8 16 32 64 128'}
 	export PERF_SYNC_TYPES=${PERF_SYNC_TYPES:-'0 1'}
 	export PERF_IOSIZES=${PERF_IOSIZES:-'8k'}
 elif [[ -n $PERF_REGRESSION_NIGHTLY ]]; then
 	export PERF_RUNTIME=${PERF_RUNTIME:-$PERF_RUNTIME_NIGHTLY}
 	export PERF_RUNTYPE=${PERF_RUNTYPE:-'nightly'}
-	export PERF_NTHREADS=${PERF_NTHREADS:-'64 128'}
+	export PERF_NTHREADS=${PERF_NTHREADS:-'32 128'}
 	export PERF_SYNC_TYPES=${PERF_SYNC_TYPES:-'1'}
 	export PERF_IOSIZES=${PERF_IOSIZES:-'8k'}
 fi
diff --git a/tests/zfs-tests/tests/perf/regression/sequential_reads.ksh b/tests/zfs-tests/tests/perf/regression/sequential_reads.ksh
index af53e5d1e..e60dbb181 100755
--- a/tests/zfs-tests/tests/perf/regression/sequential_reads.ksh
+++ b/tests/zfs-tests/tests/perf/regression/sequential_reads.ksh
@@ -25,6 +25,15 @@
 # for all fio runs. The ARC is cleared with `zinject -a` prior to each run
 # so reads will go to disk.
 #
+# Thread/Concurrency settings:
+#    PERF_NTHREADS defines the number of files created in the test filesystem,
+#    as well as the number of threads that will simultaneously drive IO to
+#    those files.  The settings chosen are from measurements in the
+#    PerfAutoESX/ZFSPerfESX Environments, selected at concurrency levels that
+#    are at peak throughput but lowest latency.  Higher concurrency introduces
+#    queue time latency and would reduce the impact of code-induced performance
+#    regressions.
+#
 
 . $STF_SUITE/include/libtest.shlib
 . $STF_SUITE/tests/perf/perf.shlib
@@ -54,13 +63,13 @@ export TOTAL_SIZE=$(($(get_prop avail $TESTFS) * 3 / 2))
 if [[ -n $PERF_REGRESSION_WEEKLY ]]; then
 	export PERF_RUNTIME=${PERF_RUNTIME:-$PERF_RUNTIME_WEEKLY}
 	export PERF_RUNTYPE=${PERF_RUNTYPE:-'weekly'}
-	export PERF_NTHREADS=${PERF_NTHREADS:-'16 64'}
+	export PERF_NTHREADS=${PERF_NTHREADS:-'8 16 32 64'}
 	export PERF_SYNC_TYPES=${PERF_SYNC_TYPES:-'1'}
 	export PERF_IOSIZES=${PERF_IOSIZES:-'64k 128k 1m'}
 elif [[ -n $PERF_REGRESSION_NIGHTLY ]]; then
 	export PERF_RUNTIME=${PERF_RUNTIME:-$PERF_RUNTIME_NIGHTLY}
 	export PERF_RUNTYPE=${PERF_RUNTYPE:-'nightly'}
-	export PERF_NTHREADS=${PERF_NTHREADS:-'64 128'}
+	export PERF_NTHREADS=${PERF_NTHREADS:-'8 16'}
 	export PERF_SYNC_TYPES=${PERF_SYNC_TYPES:-'1'}
 	export PERF_IOSIZES=${PERF_IOSIZES:-'128k 1m'}
 fi
diff --git a/tests/zfs-tests/tests/perf/regression/sequential_writes.ksh b/tests/zfs-tests/tests/perf/regression/sequential_writes.ksh
index 3319bd47c..d5fb89020 100755
--- a/tests/zfs-tests/tests/perf/regression/sequential_writes.ksh
+++ b/tests/zfs-tests/tests/perf/regression/sequential_writes.ksh
@@ -24,6 +24,15 @@
 # Prior to each fio run the dataset is recreated, and fio writes new files
 # into an otherwise empty pool.
 #
+# Thread/Concurrency settings:
+#    PERF_NTHREADS defines the number of files created in the test filesystem,
+#    as well as the number of threads that will simultaneously drive IO to
+#    those files.  The settings chosen are from measurements in the
+#    PerfAutoESX/ZFSPerfESX Environments, selected at concurrency levels that
+#    are at peak throughput but lowest latency.  Higher concurrency introduces
+#    queue time latency and would reduce the impact of code-induced performance
+#    regressions.
+#
 
 . $STF_SUITE/include/libtest.shlib
 . $STF_SUITE/tests/perf/perf.shlib
@@ -53,13 +62,13 @@ export TOTAL_SIZE=$(($(get_prop avail $TESTFS) * 3 / 2))
 if [[ -n $PERF_REGRESSION_WEEKLY ]]; then
 	export PERF_RUNTIME=${PERF_RUNTIME:-$PERF_RUNTIME_WEEKLY}
 	export PERF_RUNTYPE=${PERF_RUNTYPE:-'weekly'}
-	export PERF_NTHREADS=${PERF_NTHREADS:-'8 16'}
+	export PERF_NTHREADS=${PERF_NTHREADS:-'1 4 8 16 32 64 128'}
 	export PERF_SYNC_TYPES=${PERF_SYNC_TYPES:-'0 1'}
 	export PERF_IOSIZES=${PERF_IOSIZES:-'8k 128k 1m'}
 elif [[ -n $PERF_REGRESSION_NIGHTLY ]]; then
 	export PERF_RUNTIME=${PERF_RUNTIME:-$PERF_RUNTIME_NIGHTLY}
 	export PERF_RUNTYPE=${PERF_RUNTYPE:-'nightly'}
-	export PERF_NTHREADS=${PERF_NTHREADS:-'64 128'}
+	export PERF_NTHREADS=${PERF_NTHREADS:-'16 32'}
 	export PERF_SYNC_TYPES=${PERF_SYNC_TYPES:-'1'}
 	export PERF_IOSIZES=${PERF_IOSIZES:-'8k 128k 1m'}
 fi