diff options
| author | Minchan Kim <minchan@kernel.org> | 2014-01-30 15:46:06 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2014-01-30 16:56:56 -0800 |
| commit | e46e33152eb82b8e2db7ffb3790a2a2653c34513 (patch) | |
| tree | a55cd8329dcb0f30b11ff75605b3f4f7bbd790de /drivers/gpu | |
| parent | f614a9f48dedd2b80d1dc8bae8094842fcdb39dd (diff) | |
zram: remove zram->lock in read path and change it with mutex
Finally, we separated zram->lock dependency from 32bit stat/ table
handling so there is no reason to use rw_semaphore between read and
write path so this patch removes the lock from read path totally and
changes rw_semaphore with mutex. So, we could do
old:
read-read: OK
read-write: NO
write-write: NO
Now:
read-read: OK
read-write: OK
write-write: NO
The below data proves mixed workload performs well 11 times and there is
also enhance on write-write path because current rw-semaphore doesn't
support SPIN_ON_OWNER. It's side effect but anyway good thing for us.
Write-related tests perform better (from 61% to 1058%) but read path has
good/bad(from -2.22% to 1.45%) but they are all marginal within stddev.
CPU 12
iozone -t -T -l 12 -u 12 -r 16K -s 60M -I +Z -V 0
==Initial write ==Initial write
records: 10 records: 10
avg: 516189.16 avg: 839907.96
std: 22486.53 (4.36%) std: 47902.17 (5.70%)
max: 546970.60 max: 909910.35
min: 481131.54 min: 751148.38
==Rewrite ==Rewrite
records: 10 records: 10
avg: 509527.98 avg: 1050156.37
std: 45799.94 (8.99%) std: 40695.44 (3.88%)
max: 611574.27 max: 1111929.26
min: 443679.95 min: 980409.62
==Read ==Read
records: 10 records: 10
avg: 4408624.17 avg: 4472546.76
std: 281152.61 (6.38%) std: 163662.78 (3.66%)
max: 4867888.66 max: 4727351.03
min: 4058347.69 min: 4126520.88
==Re-read ==Re-read
records: 10 records: 10
avg: 4462147.53 avg: 4363257.75
std: 283546.11 (6.35%) std: 247292.63 (5.67%)
max: 4912894.44 max: 4677241.75
min: 4131386.50 min: 4035235.84
==Reverse Read ==Reverse Read
records: 10 records: 10
avg: 4565865.97 avg: 4485818.08
std: 313395.63 (6.86%) std: 248470.10 (5.54%)
max: 5232749.16 max: 4789749.94
min: 4185809.62 min: 3963081.34
==Stride read ==Stride read
records: 10 records: 10
avg: 4515981.80 avg: 4418806.01
std: 211192.32 (4.68%) std: 212837.97 (4.82%)
max: 4889287.28 max: 4686967.22
min: 4210362.00 min: 4083041.84
==Random read ==Random read
records: 10 records: 10
avg: 4410525.23 avg: 4387093.18
std: 236693.22 (5.37%) std: 235285.23 (5.36%)
max: 4713698.47 max: 4669760.62
min: 4057163.62 min: 3952002.16
==Mixed workload ==Mixed workload
records: 10 records: 10
avg: 243234.25 avg: 2818677.27
std: 28505.07 (11.72%) std: 195569.70 (6.94%)
max: 288905.23 max: 3126478.11
min: 212473.16 min: 2484150.69
==Random write ==Random write
records: 10 records: 10
avg: 555887.07 avg: 1053057.79
std: 70841.98 (12.74%) std: 35195.36 (3.34%)
max: 683188.28 max: 1096125.73
min: 437299.57 min: 992481.93
==Pwrite ==Pwrite
records: 10 records: 10
avg: 501745.93 avg: 810363.09
std: 16373.54 (3.26%) std: 19245.01 (2.37%)
max: 518724.52 max: 833359.70
min: 464208.73 min: 765501.87
==Pread ==Pread
records: 10 records: 10
avg: 4539894.60 avg: 4457680.58
std: 197094.66 (4.34%) std: 188965.60 (4.24%)
max: 4877170.38 max: 4689905.53
min: 4226326.03 min: 4095739.72
Signed-off-by: Minchan Kim <minchan@kernel.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Tested-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Jerome Marchand <jmarchan@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'drivers/gpu')
0 files changed, 0 insertions, 0 deletions