Re: [PATCH v2] locking/rwsem: Add reader-owned state to the owner field

From: Waiman Long
Date: Sat May 07 2016 - 23:05:00 EST


On 05/07/2016 12:56 AM, Ingo Molnar wrote:
* Waiman Long<Waiman.Long@xxxxxxx> wrote:

On a 4-socket Haswell machine running on a 4.6-rc1 based kernel, the
fio test with multithreaded randrw and randwrite tests on the same
file on a XFS partition on top of a NVDIMM were run, the aggregated
bandwidths before and after the patch were as follows:

Test BW before patch BW after patch % change
---- --------------- -------------- --------
randrw 988 MB/s 1192 MB/s +21%
randwrite 1513 MB/s 1623 MB/s +7.3%
What testcase/suite is this? I'd like to run this on other machines as well.

Thanks,

Ingo

I just used fio on a nvdimm based xfs filesystem. It is essentially like a ramfs filesystem in term of performance. Attached were config files that I used.

Cheers,
Longman
[global]
direct=1
ioengine=libaio
norandommap
randrepeat=0
bs=4K
size=1G
iodepth=1 # pmem has no queue depth
runtime=30
time_based=1
group_reporting
thread=1
gtod_reduce=1 # reduce=1 except for latency test
gtod_cpu=1


## cross-CPU combinations
numjobs=18
cpus_allowed=0-39

cpus_allowed_policy=split

[drive_0]
filename=/mnt/fio
cpus_allowed=0-17
rw=randrw

[drive_1]
filename=/mnt/fio2
cpus_allowed=18-35
rw=randrw

[global]
direct=1
ioengine=libaio
norandommap
randrepeat=0
bs=4K
size=1G
iodepth=1 # pmem has no queue depth
runtime=30
time_based=1
group_reporting
thread=1
gtod_reduce=1 # reduce=1 except for latency test
gtod_cpu=1


## cross-CPU combinations
numjobs=18
cpus_allowed=0-39

cpus_allowed_policy=split

[drive_0]
filename=/mnt/fio
cpus_allowed=0-17
rw=randwrite

[drive_1]
filename=/mnt/fio2
cpus_allowed=18-35
rw=randwrite