* Write performance 50% compared to Windows
@ 2016-11-01 10:37 Bram Matthys
2016-11-01 13:03 ` Dâniel Fraga
` (2 more replies)
0 siblings, 3 replies; 6+ messages in thread
From: Bram Matthys @ 2016-11-01 10:37 UTC (permalink / raw)
To: linux-ide
Hi,
I have a Samsung SSD 850 EVO 4TB and under Linux I'm only getting
~240MB/s write speed. On Windows it's 490MB/s (yes, without cache).
The read speed is the same on both Linux and Windows, though. Both are
512MB/s.
Any ideas what this could be? It can't be a slow SATA link as read
speed are fine. And since write performance is fine on Windows so I'm
kinda stunned. Not sure how to proceed / debug this any further.
I'm testing with dd if=/dev/zero of=/dev/sdX bs=1M count=65536
conv=fdatasync. Results are similar without the conv=fdatasync. On
Windows I test with AS SSD.
Prior to testing I do a ATA security erase to make sure the SSD isn't
clearing any cells during the benchmark. (Previously I used blkdiscard
but then realized this would only 'mark' the cells as unused so it might
do the actual erasing in the background)
I tested this both with a 4.4.0 and 4.8.4 Linux kernel. Another
machines (different hardware) has the same results. All have a SATA III
interface.
Dmesg:
[ 4.741663] ata2.00: ATA-9: Samsung SSD 850 EVO 4TB, EMT02B6Q, max
UDMA/133
[ 4.752974] ata1.00: ATA-9: Samsung SSD 850 EVO 4TB, EMT02B6Q, max
UDMA/133
# cat /sys/block/sda/device/queue_depth
31
If you need anything else let me know. Any help is welcomed.
Regards,
Bram
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: Write performance 50% compared to Windows 2016-11-01 10:37 Write performance 50% compared to Windows Bram Matthys @ 2016-11-01 13:03 ` Dâniel Fraga 2016-11-02 15:07 ` Bram Matthys [not found] ` <CAJVOszDeJSXgdMuA-f6=JDSL78SBSz+-uDNp2PX=VTjeNyz4Bg@mail.gmail.com> 2 siblings, 0 replies; 6+ messages in thread From: Dâniel Fraga @ 2016-11-01 13:03 UTC (permalink / raw) To: linux-ide On Tue, 01 Nov 2016 11:37:42 +0100 Bram Matthys <syzop@vulnscan.org> wrote: > I have a Samsung SSD 850 EVO 4TB and under Linux I'm only getting > ~240MB/s write speed. On Windows it's 490MB/s (yes, without cache). > The read speed is the same on both Linux and Windows, though. Both are > 512MB/s. Just curious: are you using the "deadline" scheduler? What file system? Ext4? -- https://exchangewar.info ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: Write performance 50% compared to Windows 2016-11-01 10:37 Write performance 50% compared to Windows Bram Matthys 2016-11-01 13:03 ` Dâniel Fraga @ 2016-11-02 15:07 ` Bram Matthys [not found] ` <CAJVOszDeJSXgdMuA-f6=JDSL78SBSz+-uDNp2PX=VTjeNyz4Bg@mail.gmail.com> 2 siblings, 0 replies; 6+ messages in thread From: Bram Matthys @ 2016-11-02 15:07 UTC (permalink / raw) To: linux-ide Bram Matthys wrote on 1-11-2016 11:37: > I have a Samsung SSD 850 EVO 4TB and under Linux I'm only getting ~240MB/s > write speed. On Windows it's 490MB/s (yes, without cache). > The read speed is the same on both Linux and Windows, though. Both are 512MB/s. > > Any ideas what this could be? It can't be a slow SATA link as read speed are > fine. And since write performance is fine on Windows so I'm kinda stunned. Not > sure how to proceed / debug this any further. > [..] I received the following reply from Samsung: "Unfortunately, there is not much we can assist you with as Samsung does not provide support for Linux operating systems." So that isn't helping much :/ Regards, Bram ^ permalink raw reply [flat|nested] 6+ messages in thread
[parent not found: <CAJVOszDeJSXgdMuA-f6=JDSL78SBSz+-uDNp2PX=VTjeNyz4Bg@mail.gmail.com>]
* Re: Write performance 50% compared to Windows [not found] ` <CAJVOszDeJSXgdMuA-f6=JDSL78SBSz+-uDNp2PX=VTjeNyz4Bg@mail.gmail.com> @ 2016-11-03 7:46 ` Bram Matthys 2016-11-03 14:43 ` Bram Matthys 0 siblings, 1 reply; 6+ messages in thread From: Bram Matthys @ 2016-11-03 7:46 UTC (permalink / raw) To: linux-ide Shaun Tancheff wrote on 2-11-2016 18:50: > On Tue, Nov 1, 2016 at 5:37 AM, Bram Matthys <syzop@vulnscan.org > <mailto:syzop@vulnscan.org>> wrote: > > Hi, > > I have a Samsung SSD 850 EVO 4TB and under Linux I'm only getting ~240MB/s > write speed. On Windows it's 490MB/s (yes, without cache). > The read speed is the same on both Linux and Windows, though. Both are > 512MB/s. > > Any ideas what this could be? It can't be a slow SATA link as read speed > are fine. And since write performance is fine on Windows so I'm kinda > stunned. Not sure how to proceed / debug this any further. > > I'm testing with dd if=/dev/zero of=/dev/sdX bs=1M count=65536 > conv=fdatasync. Results are similar without the conv=fdatasync. On Windows > I test with AS SSD. > Prior to testing I do a ATA security erase to make sure the SSD isn't > clearing any cells during the benchmark. (Previously I used blkdiscard but > then realized this would only 'mark' the cells as unused so it might do > the actual erasing in the background) > I tested this both with a 4.4.0 and 4.8.4 Linux kernel. Another machines > (different hardware) has the same results. All have a SATA III interface. > > > May I suggest that dd is unlikely to give you an accurate measurement of > throughput. > I would suggest using something like 'fio' instead. > > sudo fio --ioengine=sync --direct=1 --iodepth=32 --numjobs=1 --rw=write \ > --bsrange=1M-1M --filename=/dev/sdb --runtime=1000 --name=fio > > I routinely see 500+MB/s with the 2TB SSD I have here ... Thanks Shaun for your suggestion. I tried this and unfortunately the results are not much better with fio: To summarize, on Linux (4.8.5): * fio sync: * READ: 478MB/s * WRITE: 118MB/s * fio libaio: * READ: 511MB/s * WRITE: 163MB/s * dd: * READ: 526MB/s * WRITE: 235MB/s On Windows (7): * AS SSD http://imgur.com/ygCINXF : * READ: 512MB/s * WRITE: 493MB/s * ATTO SSD (32GB data 1M/2M/4M bsize) http://imgur.com/46cbogr : * READ: 560MB/s * WRITE: 533MB/s (And a quick ATTO block size test http://imgur.com/MhuLjno ) Output of the fio and dd commands are below. # fio --ioengine=sync --direct=1 --iodepth=32 --numjobs=1 --rw=read --bsrange=1M-1M --runtime=1000 --name=fio --filename=/dev/sda fio: (g=0): rw=read, bs=1M-1M/1M-1M/1M-1M, ioengine=sync, iodepth=32 fio-2.2.10 Starting 1 process Jobs: 1 (f=1): [R(1)] [100.0% done] [472.0MB/0KB/0KB /s] [472/0/0 iops] [eta 00m:00s] fio: (groupid=0, jobs=1): err= 0: pid=14727: Thu Nov 3 07:40:58 2016 read : io=467388MB, bw=478604KB/s, iops=467, runt=1000002msec clat (usec): min=1901, max=10352, avg=2136.75, stdev=147.57 lat (usec): min=1901, max=10353, avg=2137.03, stdev=147.59 clat percentiles (usec): | 1.00th=[ 2024], 5.00th=[ 2064], 10.00th=[ 2064], 20.00th=[ 2096], | 30.00th=[ 2128], 40.00th=[ 2128], 50.00th=[ 2128], 60.00th=[ 2128], | 70.00th=[ 2160], 80.00th=[ 2160], 90.00th=[ 2192], 95.00th=[ 2192], | 99.00th=[ 2320], 99.50th=[ 2352], 99.90th=[ 3568], 99.95th=[ 6624], | 99.99th=[ 7776] bw (KB /s): min=286147, max=495616, per=100.00%, avg=479047.45, stdev=11395.42 lat (msec) : 2=0.23%, 4=99.68%, 10=0.09%, 20=0.01% cpu : usr=0.21%, sys=5.20%, ctx=467427, majf=0, minf=265 IO depths : 1=100.0%, 2=0.0%, 4=0.0%, 8=0.0%, 16=0.0%, 32=0.0%, >=64=0.0% submit : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, 32=0.0%, 64=0.0%, >=64=0.0% complete : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, 32=0.0%, 64=0.0%, >=64=0.0% issued : total=r=467388/w=0/d=0, short=r=0/w=0/d=0, drop=r=0/w=0/d=0 latency : target=0, window=0, percentile=100.00%, depth=32 Run status group 0 (all jobs): READ: io=467388MB, aggrb=478604KB/s, minb=478604KB/s, maxb=478604KB/s, mint=1000002msec, maxt=1000002msec Disk stats (read/write): sda: ios=934688/0, merge=0/0, ticks=1594452/0, in_queue=1594292, util=95.27% # fio --ioengine=libaio --direct=1 --iodepth=32 --numjobs=1 --rw=read --bsrange=1M-1M --runtime=1000 --name=fio --filename=/dev/sda fio: (g=0): rw=read, bs=1M-1M/1M-1M/1M-1M, ioengine=libaio, iodepth=32 fio-2.2.10 Starting 1 process Jobs: 1 (f=1): [R(1)] [100.0% done] [507.0MB/0KB/0KB /s] [507/0/0 iops] [eta 00m:00s] fio: (groupid=0, jobs=1): err= 0: pid=14761: Thu Nov 3 07:58:01 2016 read : io=499290MB, bw=511241KB/s, iops=499, runt=1000062msec slat (usec): min=29, max=606, avg=56.90, stdev=21.02 clat (msec): min=5, max=148, avg=64.03, stdev= 1.71 lat (msec): min=5, max=148, avg=64.09, stdev= 1.71 clat percentiles (msec): | 1.00th=[ 63], 5.00th=[ 63], 10.00th=[ 63], 20.00th=[ 64], | 30.00th=[ 64], 40.00th=[ 64], 50.00th=[ 64], 60.00th=[ 64], | 70.00th=[ 66], 80.00th=[ 67], 90.00th=[ 67], 95.00th=[ 67], | 99.00th=[ 67], 99.50th=[ 67], 99.90th=[ 76], 99.95th=[ 78], | 99.99th=[ 123] bw (KB /s): min=406738, max=521197, per=100.00%, avg=511739.76, stdev=11240.18 lat (msec) : 10=0.01%, 20=0.01%, 50=0.01%, 100=99.97%, 250=0.03% cpu : usr=0.60%, sys=3.67%, ctx=499374, majf=0, minf=538 IO depths : 1=0.1%, 2=0.1%, 4=0.1%, 8=0.1%, 16=0.1%, 32=100.0%, >=64=0.0% submit : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, 32=0.0%, 64=0.0%, >=64=0.0% complete : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, 32=0.1%, 64=0.0%, >=64=0.0% issued : total=r=499290/w=0/d=0, short=r=0/w=0/d=0, drop=r=0/w=0/d=0 latency : target=0, window=0, percentile=100.00%, depth=32 Run status group 0 (all jobs): READ: io=499290MB, aggrb=511241KB/s, minb=511241KB/s, maxb=511241KB/s, mint=1000062msec, maxt=1000062msec Disk stats (read/write): sda: ios=514818/0, merge=0/0, ticks=32910900/0, in_queue=32911656, util=100.00% # time fio --ioengine=sync --direct=1 --iodepth=32 --numjobs=1 --rw=write --bsrange=1M-1M --runtime=1000 --name=fio --filename=/dev/sda fio: (g=0): rw=write, bs=1M-1M/1M-1M/1M-1M, ioengine=sync, iodepth=32 fio-2.2.10 Starting 1 process Jobs: 1 (f=1): [W(1)] [100.0% done] [0KB/101.0MB/0KB /s] [0/101/0 iops] [eta 00m:00s] fio: (groupid=0, jobs=1): err= 0: pid=14207: Wed Nov 2 20:48:09 2016 write: io=116047MB, bw=118831KB/s, iops=116, runt=1000006msec clat (msec): min=4, max=24, avg= 8.58, stdev= 2.26 lat (msec): min=4, max=24, avg= 8.61, stdev= 2.26 clat percentiles (usec): | 1.00th=[ 5024], 5.00th=[ 5152], 10.00th=[ 5280], 20.00th=[ 5664], | 30.00th=[ 6944], 40.00th=[ 9152], 50.00th=[ 9280], 60.00th=[ 9536], | 70.00th=[ 9792], 80.00th=[10048], 90.00th=[10560], 95.00th=[11328], | 99.00th=[14400], 99.50th=[17280], 99.90th=[19328], 99.95th=[20352], | 99.99th=[21120] bw (KB /s): min=91610, max=202752, per=100.00%, avg=119006.32, stdev=31198.56 lat (msec) : 10=79.69%, 20=20.24%, 50=0.06% cpu : usr=0.43%, sys=0.73%, ctx=116061, majf=0, minf=11 IO depths : 1=100.0%, 2=0.0%, 4=0.0%, 8=0.0%, 16=0.0%, 32=0.0%, >=64=0.0% submit : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, 32=0.0%, 64=0.0%, >=64=0.0% complete : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, 32=0.0%, 64=0.0%, >=64=0.0% issued : total=r=0/w=116047/d=0, short=r=0/w=0/d=0, drop=r=0/w=0/d=0 latency : target=0, window=0, percentile=100.00%, depth=32 Run status group 0 (all jobs): WRITE: io=116047MB, aggrb=118831KB/s, minb=118831KB/s, maxb=118831KB/s, mint=1000006msec, maxt=1000006msec Disk stats (read/write): sda: ios=0/116037, merge=0/0, ticks=0/985368, in_queue=985316, util=98.61% real 16m40.461s user 0m5.472s sys 0m8.992s # time fio --ioengine=libaio --direct=1 --iodepth=32 --numjobs=1 --rw=write --bsrange=1M-1M --runtime=1000 --name=fio --filename=/dev/sda fio: (g=0): rw=write, bs=1M-1M/1M-1M/1M-1M, ioengine=libaio, iodepth=32 fio-2.2.10 Starting 1 process Jobs: 1 (f=1): [W(1)] [100.0% done] [0KB/141.0MB/0KB /s] [0/141/0 iops] [eta 00m:00s] fio: (groupid=0, jobs=1): err= 0: pid=14469: Wed Nov 2 21:22:17 2016 write: io=159168MB, bw=162952KB/s, iops=159, runt=1000219msec slat (usec): min=34, max=621, avg=109.71, stdev=23.32 clat (msec): min=78, max=539, avg=200.98, stdev=86.51 lat (msec): min=78, max=539, avg=201.09, stdev=86.51 clat percentiles (msec): | 1.00th=[ 83], 5.00th=[ 86], 10.00th=[ 89], 20.00th=[ 105], | 30.00th=[ 176], 40.00th=[ 188], 50.00th=[ 200], 60.00th=[ 212], | 70.00th=[ 227], 80.00th=[ 237], 90.00th=[ 255], 95.00th=[ 408], | 99.00th=[ 469], 99.50th=[ 482], 99.90th=[ 498], 99.95th=[ 502], | 99.99th=[ 519] bw (KB /s): min=104160, max=389120, per=100.00%, avg=166894.31, stdev=63045.67 lat (msec) : 100=19.30%, 250=69.43%, 500=11.20%, 750=0.08% cpu : usr=0.97%, sys=0.83%, ctx=5748, majf=0, minf=11 IO depths : 1=0.1%, 2=0.1%, 4=0.1%, 8=0.1%, 16=0.1%, 32=100.0%, >=64=0.0% submit : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, 32=0.0%, 64=0.0%, >=64=0.0% complete : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, 32=0.1%, 64=0.0%, >=64=0.0% issued : total=r=0/w=159168/d=0, short=r=0/w=0/d=0, drop=r=0/w=0/d=0 latency : target=0, window=0, percentile=100.00%, depth=32 Run status group 0 (all jobs): WRITE: io=159168MB, aggrb=162952KB/s, minb=162952KB/s, maxb=162952KB/s, mint=1000219msec, maxt=1000219msec Disk stats (read/write): sda: ios=0/159136, merge=0/0, ticks=0/31683824, in_queue=31685776, util=100.00% real 16m40.684s user 0m10.840s sys 0m9.996s # time dd if=/dev/zero of=/dev/sda bs=1M count=65536 conv=fdatasync 65536+0 records in 65536+0 records out 68719476736 bytes (69 GB, 64 GiB) copied, 292.338 s, 235 MB/s real 4m52.342s user 0m0.024s sys 0m38.048s # echo 3 >/proc/sys/vm/drop_caches # time dd if=/dev/sda of=/dev/null bs=1M count=65536 65536+0 records in 65536+0 records out 68719476736 bytes (69 GB, 64 GiB) copied, 130.537 s, 526 MB/s real 2m10.543s user 0m0.028s sys 0m28.604s ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: Write performance 50% compared to Windows 2016-11-03 7:46 ` Bram Matthys @ 2016-11-03 14:43 ` Bram Matthys 0 siblings, 0 replies; 6+ messages in thread From: Bram Matthys @ 2016-11-03 14:43 UTC (permalink / raw) To: linux-ide Bram Matthys schreef op 2016-11-03 08:46: > Shaun Tancheff wrote on 2-11-2016 18:50: >> On Tue, Nov 1, 2016 at 5:37 AM, Bram Matthys <syzop@vulnscan.org >> <mailto:syzop@vulnscan.org>> wrote: >> >> Hi, >> >> I have a Samsung SSD 850 EVO 4TB and under Linux I'm only >> getting ~240MB/s >> write speed. On Windows it's 490MB/s (yes, without cache). >> The read speed is the same on both Linux and Windows, though. >> Both are >> 512MB/s. >> >> Any ideas what this could be? It can't be a slow SATA link as >> read speed >> are fine. And since write performance is fine on Windows so I'm >> kinda >> stunned. Not sure how to proceed / debug this any further. >> >> I'm testing with dd if=/dev/zero of=/dev/sdX bs=1M count=65536 >> conv=fdatasync. Results are similar without the conv=fdatasync. >> On Windows >> I test with AS SSD. >> Prior to testing I do a ATA security erase to make sure the SSD >> isn't >> clearing any cells during the benchmark. (Previously I used >> blkdiscard but >> then realized this would only 'mark' the cells as unused so it >> might do >> the actual erasing in the background) >> I tested this both with a 4.4.0 and 4.8.4 Linux kernel. Another >> machines >> (different hardware) has the same results. All have a SATA III >> interface. >> >> >> May I suggest that dd is unlikely to give you an accurate >> measurement of >> throughput. >> I would suggest using something like 'fio' instead. >> >> sudo fio --ioengine=sync --direct=1 --iodepth=32 --numjobs=1 >> --rw=write \ >> --bsrange=1M-1M --filename=/dev/sdb --runtime=1000 --name=fio >> >> I routinely see 500+MB/s with the 2TB SSD I have here ... > > Thanks Shaun for your suggestion. I tried this and unfortunately the > results are not much better with fio: > > To summarize, on Linux (4.8.5): > * fio sync: > * READ: 478MB/s > * WRITE: 118MB/s > * fio libaio: > * READ: 511MB/s > * WRITE: 163MB/s > * dd: > * READ: 526MB/s > * WRITE: 235MB/s I just installed FreeBSD on the system for testing purposes and I'm getting 444MB/s write speed. That's almost double of Linux. root@fbsd:/dev # time dd if=/dev/zero of=/dev/ada1 bs=1M count=131072 conv=sync 131072+0 records in 131072+0 records out 137438953472 bytes transferred in 308.931389 secs (444885041 bytes/sec) 12.941u 27.742s 5:08.93 12.1% 29+169k 0+1048576io 0pf+0w Sorry didn't have fio on the system, but in in any case the 444MB/s is a minimum. Read speed is 500MB/s by the way. So this slow write performance issue seems Linux-specific. Any (other) tips to get write speeds at the same level as FreeBSD or Windows would be highly appreciated. Regards, Bram > > On Windows (7): > * AS SSD http://imgur.com/ygCINXF : > * READ: 512MB/s > * WRITE: 493MB/s > * ATTO SSD (32GB data 1M/2M/4M bsize) http://imgur.com/46cbogr : > * READ: 560MB/s > * WRITE: 533MB/s > (And a quick ATTO block size test http://imgur.com/MhuLjno ) > > Output of the fio and dd commands are below. > > # fio --ioengine=sync --direct=1 --iodepth=32 --numjobs=1 --rw=read > --bsrange=1M-1M --runtime=1000 --name=fio --filename=/dev/sda > fio: (g=0): rw=read, bs=1M-1M/1M-1M/1M-1M, ioengine=sync, iodepth=32 > fio-2.2.10 > Starting 1 process > Jobs: 1 (f=1): [R(1)] [100.0% done] [472.0MB/0KB/0KB /s] [472/0/0 > iops] [eta 00m:00s] > fio: (groupid=0, jobs=1): err= 0: pid=14727: Thu Nov 3 07:40:58 2016 > read : io=467388MB, bw=478604KB/s, iops=467, runt=1000002msec > clat (usec): min=1901, max=10352, avg=2136.75, stdev=147.57 > lat (usec): min=1901, max=10353, avg=2137.03, stdev=147.59 > clat percentiles (usec): > | 1.00th=[ 2024], 5.00th=[ 2064], 10.00th=[ 2064], 20.00th=[ > 2096], > | 30.00th=[ 2128], 40.00th=[ 2128], 50.00th=[ 2128], 60.00th=[ > 2128], > | 70.00th=[ 2160], 80.00th=[ 2160], 90.00th=[ 2192], 95.00th=[ > 2192], > | 99.00th=[ 2320], 99.50th=[ 2352], 99.90th=[ 3568], 99.95th=[ > 6624], > | 99.99th=[ 7776] > bw (KB /s): min=286147, max=495616, per=100.00%, avg=479047.45, > stdev=11395.42 > lat (msec) : 2=0.23%, 4=99.68%, 10=0.09%, 20=0.01% > cpu : usr=0.21%, sys=5.20%, ctx=467427, majf=0, minf=265 > IO depths : 1=100.0%, 2=0.0%, 4=0.0%, 8=0.0%, 16=0.0%, 32=0.0%, > >=64=0.0% > submit : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, 32=0.0%, 64=0.0%, > >=64=0.0% > complete : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, 32=0.0%, 64=0.0%, > >=64=0.0% > issued : total=r=467388/w=0/d=0, short=r=0/w=0/d=0, > drop=r=0/w=0/d=0 > latency : target=0, window=0, percentile=100.00%, depth=32 > > Run status group 0 (all jobs): > READ: io=467388MB, aggrb=478604KB/s, minb=478604KB/s, > maxb=478604KB/s, mint=1000002msec, maxt=1000002msec > > Disk stats (read/write): > sda: ios=934688/0, merge=0/0, ticks=1594452/0, in_queue=1594292, > util=95.27% > > # fio --ioengine=libaio --direct=1 --iodepth=32 --numjobs=1 --rw=read > --bsrange=1M-1M --runtime=1000 --name=fio --filename=/dev/sda > fio: (g=0): rw=read, bs=1M-1M/1M-1M/1M-1M, ioengine=libaio, > iodepth=32 > fio-2.2.10 > Starting 1 process > Jobs: 1 (f=1): [R(1)] [100.0% done] [507.0MB/0KB/0KB /s] [507/0/0 > iops] [eta 00m:00s] > fio: (groupid=0, jobs=1): err= 0: pid=14761: Thu Nov 3 07:58:01 2016 > read : io=499290MB, bw=511241KB/s, iops=499, runt=1000062msec > slat (usec): min=29, max=606, avg=56.90, stdev=21.02 > clat (msec): min=5, max=148, avg=64.03, stdev= 1.71 > lat (msec): min=5, max=148, avg=64.09, stdev= 1.71 > clat percentiles (msec): > | 1.00th=[ 63], 5.00th=[ 63], 10.00th=[ 63], 20.00th=[ > 64], > | 30.00th=[ 64], 40.00th=[ 64], 50.00th=[ 64], 60.00th=[ > 64], > | 70.00th=[ 66], 80.00th=[ 67], 90.00th=[ 67], 95.00th=[ > 67], > | 99.00th=[ 67], 99.50th=[ 67], 99.90th=[ 76], 99.95th=[ > 78], > | 99.99th=[ 123] > bw (KB /s): min=406738, max=521197, per=100.00%, avg=511739.76, > stdev=11240.18 > lat (msec) : 10=0.01%, 20=0.01%, 50=0.01%, 100=99.97%, 250=0.03% > cpu : usr=0.60%, sys=3.67%, ctx=499374, majf=0, minf=538 > IO depths : 1=0.1%, 2=0.1%, 4=0.1%, 8=0.1%, 16=0.1%, 32=100.0%, > >=64=0.0% > submit : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, 32=0.0%, 64=0.0%, > >=64=0.0% > complete : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, 32=0.1%, 64=0.0%, > >=64=0.0% > issued : total=r=499290/w=0/d=0, short=r=0/w=0/d=0, > drop=r=0/w=0/d=0 > latency : target=0, window=0, percentile=100.00%, depth=32 > > Run status group 0 (all jobs): > READ: io=499290MB, aggrb=511241KB/s, minb=511241KB/s, > maxb=511241KB/s, mint=1000062msec, maxt=1000062msec > > Disk stats (read/write): > sda: ios=514818/0, merge=0/0, ticks=32910900/0, in_queue=32911656, > util=100.00% > > # time fio --ioengine=sync --direct=1 --iodepth=32 --numjobs=1 > --rw=write --bsrange=1M-1M --runtime=1000 --name=fio > --filename=/dev/sda > fio: (g=0): rw=write, bs=1M-1M/1M-1M/1M-1M, ioengine=sync, iodepth=32 > fio-2.2.10 > Starting 1 process > Jobs: 1 (f=1): [W(1)] [100.0% done] [0KB/101.0MB/0KB /s] [0/101/0 > iops] [eta 00m:00s] > fio: (groupid=0, jobs=1): err= 0: pid=14207: Wed Nov 2 20:48:09 2016 > write: io=116047MB, bw=118831KB/s, iops=116, runt=1000006msec > clat (msec): min=4, max=24, avg= 8.58, stdev= 2.26 > lat (msec): min=4, max=24, avg= 8.61, stdev= 2.26 > clat percentiles (usec): > | 1.00th=[ 5024], 5.00th=[ 5152], 10.00th=[ 5280], 20.00th=[ > 5664], > | 30.00th=[ 6944], 40.00th=[ 9152], 50.00th=[ 9280], 60.00th=[ > 9536], > | 70.00th=[ 9792], 80.00th=[10048], 90.00th=[10560], > 95.00th=[11328], > | 99.00th=[14400], 99.50th=[17280], 99.90th=[19328], > 99.95th=[20352], > | 99.99th=[21120] > bw (KB /s): min=91610, max=202752, per=100.00%, avg=119006.32, > stdev=31198.56 > lat (msec) : 10=79.69%, 20=20.24%, 50=0.06% > cpu : usr=0.43%, sys=0.73%, ctx=116061, majf=0, minf=11 > IO depths : 1=100.0%, 2=0.0%, 4=0.0%, 8=0.0%, 16=0.0%, 32=0.0%, > >=64=0.0% > submit : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, 32=0.0%, 64=0.0%, > >=64=0.0% > complete : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, 32=0.0%, 64=0.0%, > >=64=0.0% > issued : total=r=0/w=116047/d=0, short=r=0/w=0/d=0, > drop=r=0/w=0/d=0 > latency : target=0, window=0, percentile=100.00%, depth=32 > > Run status group 0 (all jobs): > WRITE: io=116047MB, aggrb=118831KB/s, minb=118831KB/s, > maxb=118831KB/s, mint=1000006msec, maxt=1000006msec > > Disk stats (read/write): > sda: ios=0/116037, merge=0/0, ticks=0/985368, in_queue=985316, > util=98.61% > > real 16m40.461s > user 0m5.472s > sys 0m8.992s > > # time fio --ioengine=libaio --direct=1 --iodepth=32 --numjobs=1 > --rw=write --bsrange=1M-1M --runtime=1000 --name=fio > --filename=/dev/sda > fio: (g=0): rw=write, bs=1M-1M/1M-1M/1M-1M, ioengine=libaio, > iodepth=32 > fio-2.2.10 > Starting 1 process > Jobs: 1 (f=1): [W(1)] [100.0% done] [0KB/141.0MB/0KB /s] [0/141/0 > iops] [eta 00m:00s] > fio: (groupid=0, jobs=1): err= 0: pid=14469: Wed Nov 2 21:22:17 2016 > write: io=159168MB, bw=162952KB/s, iops=159, runt=1000219msec > slat (usec): min=34, max=621, avg=109.71, stdev=23.32 > clat (msec): min=78, max=539, avg=200.98, stdev=86.51 > lat (msec): min=78, max=539, avg=201.09, stdev=86.51 > clat percentiles (msec): > | 1.00th=[ 83], 5.00th=[ 86], 10.00th=[ 89], 20.00th=[ > 105], > | 30.00th=[ 176], 40.00th=[ 188], 50.00th=[ 200], 60.00th=[ > 212], > | 70.00th=[ 227], 80.00th=[ 237], 90.00th=[ 255], 95.00th=[ > 408], > | 99.00th=[ 469], 99.50th=[ 482], 99.90th=[ 498], 99.95th=[ > 502], > | 99.99th=[ 519] > bw (KB /s): min=104160, max=389120, per=100.00%, avg=166894.31, > stdev=63045.67 > lat (msec) : 100=19.30%, 250=69.43%, 500=11.20%, 750=0.08% > cpu : usr=0.97%, sys=0.83%, ctx=5748, majf=0, minf=11 > IO depths : 1=0.1%, 2=0.1%, 4=0.1%, 8=0.1%, 16=0.1%, 32=100.0%, > >=64=0.0% > submit : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, 32=0.0%, 64=0.0%, > >=64=0.0% > complete : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, 32=0.1%, 64=0.0%, > >=64=0.0% > issued : total=r=0/w=159168/d=0, short=r=0/w=0/d=0, > drop=r=0/w=0/d=0 > latency : target=0, window=0, percentile=100.00%, depth=32 > > Run status group 0 (all jobs): > WRITE: io=159168MB, aggrb=162952KB/s, minb=162952KB/s, > maxb=162952KB/s, mint=1000219msec, maxt=1000219msec > > Disk stats (read/write): > sda: ios=0/159136, merge=0/0, ticks=0/31683824, in_queue=31685776, > util=100.00% > > real 16m40.684s > user 0m10.840s > sys 0m9.996s > > # time dd if=/dev/zero of=/dev/sda bs=1M count=65536 conv=fdatasync > 65536+0 records in > 65536+0 records out > 68719476736 bytes (69 GB, 64 GiB) copied, 292.338 s, 235 MB/s > > real 4m52.342s > user 0m0.024s > sys 0m38.048s > > # echo 3 >/proc/sys/vm/drop_caches > > # time dd if=/dev/sda of=/dev/null bs=1M count=65536 > 65536+0 records in > 65536+0 records out > 68719476736 bytes (69 GB, 64 GiB) copied, 130.537 s, 526 MB/s > > real 2m10.543s > user 0m0.028s > sys 0m28.604s > > -- > To unsubscribe from this list: send the line "unsubscribe linux-ide" > in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: Write performance 50% compared to Windows
@ 2016-11-01 13:55 Bram Matthys
0 siblings, 0 replies; 6+ messages in thread
From: Bram Matthys @ 2016-11-01 13:55 UTC (permalink / raw)
To: linux-ide
Hi Daniel,
Daniel Fraga schreef op 2016-11-01 14:03:
> On Tue, 01 Nov 2016 11:37:42 +0100
> Bram Matthys <syzop@vulnscan.org> wrote:
>
>> I have a Samsung SSD 850 EVO 4TB and under Linux I'm only getting
>> ~240MB/s write speed. On Windows it's 490MB/s (yes, without cache).
>> The read speed is the same on both Linux and Windows, though. Both
>> are
>> 512MB/s.
>
> Just curious: are you using the "deadline" scheduler? What file
> system? Ext4?
Yes, the deadline scheduler.
On Linux I'm writing directly to /dev/sda, no file system.
Regards,
Bram
^ permalink raw reply [flat|nested] 6+ messages in threadend of thread, other threads:[~2016-11-03 14:43 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2016-11-01 10:37 Write performance 50% compared to Windows Bram Matthys
2016-11-01 13:03 ` Dâniel Fraga
2016-11-02 15:07 ` Bram Matthys
[not found] ` <CAJVOszDeJSXgdMuA-f6=JDSL78SBSz+-uDNp2PX=VTjeNyz4Bg@mail.gmail.com>
2016-11-03 7:46 ` Bram Matthys
2016-11-03 14:43 ` Bram Matthys
-- strict thread matches above, loose matches on Subject: below --
2016-11-01 13:55 Bram Matthys
This is a public inbox, see mirroring instructions for how to clone and mirror all data and code used for this inbox; as well as URLs for NNTP newsgroup(s).