Hello,
On (03/31/16 07:12), Minchan Kim wrote:
[..]
> > I used a bit different script. no `buffer_compress_percentage' option,
> > because it provide "a mix of random data and zeroes"
>
> Normally, zram's compression ratio is 3 or 2 so I used it.
> Hmm, isn't it more real practice usecase?
this option guarantees that the supplied to zram data will have
a requested compression ratio? hm, but we never do that in real
life, zram sees random data.
> If we don't use buffer_compress_percentage, what's the content in the buffer?
that's a good question. I quickly looked into the fio source code,
we need to use "buffer_pattern=str" option, I think. so the buffers
will be filled with the same data.
I don't mind to have buffer_compress_percentage as a separate test (set
as a local test option), but I think that using common buffer pattern
adds more confidence when we compare test results.
[..]
> > hm, but I guess it's not enough; fio probably will have different
> > data (well, only if we didn't ask it to zero-fill the buffers) for
> > different tests, causing different zram->zsmalloc behaviour. need
> > to check it.
[..]
> > #jobs4
> > READ: 8720.4MB/s 7301.7MB/s 7896.2MB/s
> > READ: 7510.3MB/s 6690.1MB/s 6456.2MB/s
> > WRITE: 2211.6MB/s 1930.8MB/s 2713.9MB/s
> > WRITE: 2002.2MB/s 1629.8MB/s 2227.7MB/s
>
> Your case is 40% win. It's huge, Nice!
> I tested with your guide line(i.e., no buffer_compress_percentage,
> scramble_buffers=0) but still 10% enhance in my machine.
> Hmm,,,
>
> How about if you test my fio job.file in your machine?
> Still, it's 40% win?
I'll retest with new config.
> Also, I want to test again in your exactly same configuration.
> Could you tell me zram environment(ie, disksize, compression
> algorithm) and share me your job.file of fio?
sure.
3G, lzo
--- my fio-template is
[global]
bs=4k
ioengine=sync
direct=1
size=__SIZE__
numjobs=__JOBS__
group_reporting
filename=/dev/zram0
loops=1
buffer_pattern=0xbadc0ffee
scramble_buffers=0
[seq-read]
rw=read
stonewall
[rand-read]
rw=randread
stonewall
[seq-write]
rw=write
stonewall
[rand-write]
rw=randwrite
stonewall
[mixed-seq]
rw=rw
stonewall
[mixed-rand]
rw=randrw
stonewall
#separate test with
#buffer_compress_percentage=50
--- my create-zram script is as follows.
#!/bin/sh
rmmod zram
modprobe zram
if [ -e /sys/block/zram0/initstate ]; then
initdone=`cat /sys/block/zram0/initstate`
if [ $initdone = 1 ]; then
echo "init done"
exit 1
fi
fi
echo 8 > /sys/block/zram0/max_comp_streams
echo lzo > /sys/block/zram0/comp_algorithm
cat /sys/block/zram0/comp_algorithm
cat /sys/block/zram0/max_comp_streams
echo $1 > /sys/block/zram0/disksize
--- and I use it as
#!/bin/sh
DEVICE_SZ=$((3 * 1024 * 1024 * 1024))
FREE_SPACE=$(($DEVICE_SZ / 10))
LOG=/tmp/fio-zram-test
LOG_SUFFIX=$1
function reset_zram
{
rmmod zram
}
function create_zram
{
./create-zram $DEVICE_SZ
}
function main
{
local j
local i
if [ "z$LOG_SUFFIX" = "z" ]; then
LOG_SUFFIX="UNSET"
fi
LOG=$LOG-$LOG_SUFFIX
for i in {1..10}; do
reset_zram
create_zram
cat fio-test-template | sed s/__JOBS__/$i/ | sed
s/__SIZE__/$((($DEVICE_SZ/$i - $FREE_SPACE)/(1024*1024)))M/ > fio-test
echo "#jobs$i" >> $LOG
time fio ./fio-test >> $LOG
done
reset_zram
}
main
-- then I use this simple script
#!/bin/sh
if [ "z$2" = "z" ]; then
cat $1 | egrep "#jobs|READ|WRITE" | awk '{printf "%-15s %15s\n", $1,
$3}' | sed s/aggrb=// | sed s/,//
else
cat $1 | egrep "#jobs|READ|WRITE" | awk '{printf " %-15s\n", $3}' | sed
s/aggrb=// | sed s/\#jobs[0-9]*// | sed s/,//
fi
as
./squeeze.sh fio-zram-test-4-stream > 4s
./squeeze.sh fio-zram-test-8-stream A > 8s
./squeeze.sh fio-zram-test-per-cpu A > pc
and
paste 4s 8s pc > result
-ss
