On Thu, Aug 02, 2012 at 11:21:51PM +0200, Martin Steigerwald wrote:
> > Yep, my du -sh tests do show that ext4 is 2x faster than btrfs.
> > Obviously it's sending IO in a way that either the IO subsystem, linux
> > driver, or drive prefer.
>
> But only on reads.
Yes. I was focussing on the simple case. SSDs can be slower than hard
drives on writes, and now you're getting into deep firmware magic for
corner cases, so I didn't want to touch that here :)
> WTF?
>
> Hey, did you adapt the size= keyword? It seems fio 2.0.8 can do completely
> without it.
I left it as is:
[global]
ioengine=libaio
direct=1
filename=/dev/sda
size=476940m
bsrange=2k-16k
[zufälliglesen]
rw=randread
runtime=60
[sequentielllesen]
stonewall
rw=read
runtime=60
I just removed it now.
> Okay, one further idea: Remove the bsrange to just test with 4k blocks.
Ok, there you go:
[global]
ioengine=libaio
direct=1
filename=/dev/sda
blocksize=4k
blockalign=4k
[zufälliglesen]
rw=randread
runtime=60
[sequentielllesen]
stonewall
rw=read
runtime=60
gandalfthegreat:~# fio --readonly ./fio.job4
zufälliglesen: (g=0): rw=randread, bs=4K-4K/4K-4K, ioengine=libaio, iodepth=1
sequentielllesen: (g=1): rw=read, bs=4K-4K/4K-4K, ioengine=libaio, iodepth=1
2.0.8
Starting 2 processes
Jobs: 1 (f=1): [_R] [66.9% done] [1476K/0K /s] [369 /0 iops] [eta 01m:00s]
zufälliglesen: (groupid=0, jobs=1): err= 0: pid=3614
read : io=60832KB, bw=1013.7KB/s, iops=253 , runt= 60012msec
slat (usec): min=4 , max=892 , avg=24.36, stdev=16.05
clat (usec): min=2 , max=27575 , avg=3915.39, stdev=4990.69
lat (usec): min=44 , max=27591 , avg=3940.35, stdev=4991.99
clat percentiles (usec):
| 1.00th=[ 41], 5.00th=[ 46], 10.00th=[ 51], 20.00th=[ 66],
| 30.00th=[ 113], 40.00th=[ 163], 50.00th=[ 205], 60.00th=[ 4960],
| 70.00th=[ 5856], 80.00th=[11584], 90.00th=[12480], 95.00th=[12608],
| 99.00th=[14272], 99.50th=[17280], 99.90th=[18816], 99.95th=[21120],
| 99.99th=[22912]
bw (KB/s) : min= 253, max= 2520, per=100.00%, avg=1014.86, stdev=364.74
lat (usec) : 4=0.05%, 10=0.01%, 20=0.01%, 50=8.07%, 100=1iiiiiiii9.94%
lat (usec) : 250=26.26%, 500=2.78%, 750=0.30%, 1000=0.09%
lat (msec) : 2=0.12%, 4=0.07%, 10=20.75%, 20=21.51%, 50=0.05%
cpu : usr=0.31%, sys=0.88%, ctx=15250, majf=0, minf=23
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=15208/w=0/d=0, short=r=0/w=0/d=0
sequentielllesen: (groupid=1, jobs=1): err= 0: pid=3636
read : io=88468KB, bw=1474.3KB/s, iops=368 , runt= 60009msec
slat (usec): min=3 , max=340 , avg=16.46, stdev=10.23
clat (usec): min=1 , max=27356 , avg=2692.99, stdev=4564.76
lat (usec): min=30 , max=27370 , avg=2709.87, stdev=4566.31
clat percentiles (usec):
| 1.00th=[ 27], 5.00th=[ 29], 10.00th=[ 31], 20.00th=[ 35],
| 30.00th=[ 47], 40.00th=[ 61], 50.00th=[ 78], 60.00th=[ 107],
| 70.00th=[ 270], 80.00th=[ 5856], 90.00th=[11712], 95.00th=[12608],
| 99.00th=[16512], 99.50th=[17536], 99.90th=[18816], 99.95th=[19584],
| 99.99th=[21120]
bw (KB/s) : min= 282, max= 5096, per=100.00%, avg=1474.40, stdev=899.36
lat (usec) : 2=0.05%, 4=0.01%, 20=0.02%, 50=32.45%, 100=24.61%
lat (usec) : 250=12.52%, 500=1.40%, 750=0.03%, 1000=0.03%
lat (msec) : 2=0.02%, 4=0.03%, 10=13.95%, 20=14.85%, 50=0.03%
cpu : usr=0.33%, sys=0.90%, ctx=22176, majf=0, minf=25
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=22117/w=0/d=0, short=r=0/w=0/d=0
Run status group 0 (all jobs):
READ: io=60832KB, aggrb=1013KB/s, minb=1013KB/s, maxb=1013KB/s, mint=60012msec, maxt=60012msec
Run status group 1 (all jobs):
READ: io=88468KB, aggrb=1474KB/s, minb=1474KB/s, maxb=1474KB/s, mint=60009msec, maxt=60009msec
Disk stats (read/write):
sda: ios=54013/1836, merge=291/17, ticks=251660/11052, in_queue=262668, util=99.51%
and the same test with blockalign=512k:
gandalfthegreat:~# fio --readonly ./fio.job4 # blockalign=512k
fio: Any use of blockalign= turns off randommap
zufälliglesen: (g=0): rw=randread, bs=4K-4K/4K-4K, ioengine=libaio, iodepth=1
sequentielllesen: (g=1): rw=read, bs=4K-4K/4K-4K, ioengine=libaio, iodepth=1
2.0.8
Starting 2 processes
Jobs: 1 (f=1): [_R] [66.9% done] [4180K/0K /s] [1045 /0 iops] [eta 01m:00s]
zufälliglesen: (groupid=0, jobs=1): err= 0: pid=3679
read : io=56096KB, bw=957355 B/s, iops=233 , runt= 60001msec
slat (usec): min=4 , max=344 , avg=27.73, stdev=15.51
clat (usec): min=2 , max=38954 , avg=4244.27, stdev=5153.32
lat (usec): min=44 , max=38980 , avg=4272.70, stdev=5154.68
clat percentiles (usec):
| 1.00th=[ 42], 5.00th=[ 46], 10.00th=[ 53], 20.00th=[ 69],
| 30.00th=[ 120], 40.00th=[ 169], 50.00th=[ 211], 60.00th=[ 5024],
| 70.00th=[ 5920], 80.00th=[11584], 90.00th=[12480], 95.00th=[12608],
| 99.00th=[16768], 99.50th=[17536], 99.90th=[18560], 99.95th=[20096],
| 99.99th=[37632]
bw (KB/s) : min= 263, max= 3133, per=100.00%, avg=935.09, stdev=392.66
lat (usec) : 4=0.05%, 10=0.03%, 20=0.01%, 50=7.84%, 100=19.12%
lat (usec) : 250=25.84%, 500=1.61%, 750=0.08%, 1000=0.05%
lat (msec) : 2=0.06%, 4=0.08%, 10=21.99%, 20=23.17%, 50=0.06%
cpu : usr=0.29%, sys=0.94%, ctx=14069, majf=0, minf=25
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=14024/w=0/d=0, short=r=0/w=0/d=0
sequentielllesen: (groupid=1, jobs=1): err= 0: pid=3703
read : io=99592KB, bw=1659.7KB/s, iops=414 , runt= 60008msec
slat (usec): min=4 , max=186 , avg=15.83, stdev= 9.95
clat (usec): min=1 , max=25530 , avg=2390.79, stdev=4340.79
lat (usec): min=28 , max=25539 , avg=2407.01, stdev=4342.90
clat percentiles (usec):
| 1.00th=[ 26], 5.00th=[ 28], 10.00th=[ 30], 20.00th=[ 34],
| 30.00th=[ 43], 40.00th=[ 57], 50.00th=[ 72], 60.00th=[ 91],
| 70.00th=[ 155], 80.00th=[ 5152], 90.00th=[11712], 95.00th=[12480],
| 99.00th=[12992], 99.50th=[16768], 99.90th=[18560], 99.95th=[18816],
| 99.99th=[21632]
bw (KB/s) : min= 269, max= 8465, per=100.00%, avg=1663.84, stdev=1367.82
lat (usec) : 2=0.01%, 4=0.02%, 20=0.01%, 50=35.42%, 100=26.00%
lat (usec) : 250=11.29%, 500=1.31%, 750=0.05%, 1000=0.01%
lat (msec) : 2=0.04%, 4=0.02%, 10=12.55%, 20=13.25%, 50=0.01%
cpu : usr=0.31%, sys=0.99%, ctx=24963, majf=0, minf=25
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=24898/w=0/d=0, short=r=0/w=0/d=0
Run status group 0 (all jobs):
READ: io=56096KB, aggrb=934KB/s, minb=934KB/s, maxb=934KB/s, mint=60001msec, maxt=60001msec
Run status group 1 (all jobs):
READ: io=99592KB, aggrb=1659KB/s, minb=1659KB/s, maxb=1659KB/s, mint=60008msec, maxt=60008msec
Disk stats (read/write):
sda: ios=55021/1637, merge=72/39, ticks=240896/12080, in_queue=252912, util=99.59%
> > Since I've gotten 2 SSDs to make sure I didn't get one bad one, and that the
> > company is greating great reviews for them, I'm now pretty sure that
> > it's either a problem with a linux driver, which is interesting for us
> > all to debug :)
>
> Either that or there possible is some firmware update? But then those
> reviews would mention it I bet.
So far, there are no firmware updates from mine, I checked right after
unboxing it :)
> > I'll try plugging this SSD in a totally different PC and see what happens.
> > This may say if it's an AHCI/intel sata driver problem.
>
> Seems we will continue until someone starts to complain here. Maybe
> another list will be more approbiate? But then this thread has it all
> in one ;). Adding a CC with some introductory note might be approbiate.
> Its your problem, so you decide ;). I´d suggest the fio mailing list,
> there are other performance people how may want to chime in.
Actually you know the lists and people involved more than me. I'd be
happy if you added a Cc to another list you think is best, and we can
move there.
> Another idea: Is there anything funny in SMART values (smartctl -a
> and possibly even -x)? Well I gather these SSDs are new, but still.
smartctl -a /dev/sda
(snipped)
SMART Attributes Data Structure revision number: 1
Vendor Specific SMART Attributes with Thresholds:
ID# ATTRIBUTE_NAME FLAG VALUE WORST THRESH TYPE UPDATED WHEN_FAILED RAW_VALUE
5 Reallocated_Sector_Ct 0x0033 100 100 010 Pre-fail Always - 0
9 Power_On_Hours 0x0032 099 099 000 Old_age Always - 36
12 Power_Cycle_Count 0x0032 099 099 000 Old_age Always - 7
177 Wear_Leveling_Count 0x0013 099 099 000 Pre-fail Always - 9
179 Used_Rsvd_Blk_Cnt_Tot 0x0013 100 100 010 Pre-fail Always - 0
181 Program_Fail_Cnt_Total 0x0032 100 100 010 Old_age Always - 0
182 Erase_Fail_Count_Total 0x0032 100 100 010 Old_age Always - 0
183 Runtime_Bad_Block 0x0013 100 100 010 Pre-fail Always - 0
187 Reported_Uncorrect 0x0032 100 100 000 Old_age Always - 0
190 Airflow_Temperature_Cel 0x0032 058 040 000 Old_age Always - 42
195 Hardware_ECC_Recovered 0x001a 200 200 000 Old_age Always - 0
199 UDMA_CRC_Error_Count 0x003e 253 253 000 Old_age Always - 0
235 Unknown_Attribute 0x0012 099 099 000 Old_age Always - 4
241 Total_LBAs_Written 0x0032 099 099 000 Old_age Always - 433339112
smartctl -x /dev/sda
smartctl 5.41 2011-06-09 r3365 [x86_64-linux-3.5.0-amd64-preempt-noide-20120410] (local build)
Copyright (C) 2002-11 by Bruce Allen, http://smartmontools.sourceforge.net
=== START OF INFORMATION SECTION ===
Device Model: SAMSUNG SSD 830 Series
Serial Number: S0WGNEAC400484
LU WWN Device Id: 5 002538 043584d30
Firmware Version: CXM03B1Q
User Capacity: 512,110,190,592 bytes [512 GB]
Sector Size: 512 bytes logical/physical
Device is: Not in smartctl database [for details use: -P showall]
ATA Version is: 8
ATA Standard is: ACS-2 revision 2
Local Time is: Thu Aug 2 14:42:08 2012 PDT
SMART support is: Available - device has SMART capability.
SMART support is: Enabled
=== START OF READ SMART DATA SECTION ===
SMART overall-health self-assessment test result: PASSED
General SMART Values:
Offline data collection status: (0x83) Offline data collection activity
is in a Reserved state.
Auto Offline Data Collection: Enabled.
Self-test execution status: ( 0) The previous self-test routine completed
without error or no self-test has ever
been run.
Total time to complete Offline
data collection: ( 1980) seconds.
Offline data collection
capabilities: (0x5b) SMART execute Offline immediate.
Auto Offline data collection on/off support.
Suspend Offline collection upon new
command.
Offline surface scan supported.
Self-test supported.
No Conveyance Self-test supported.
Selective Self-test supported.
SMART capabilities: (0x0003) Saves SMART data before entering
power-saving mode.
Supports SMART auto save timer.
Error logging capability: (0x01) Error logging supported.
General Purpose Logging supported.
Short self-test routine
recommended polling time: ( 2) minutes.
Extended self-test routine
recommended polling time: ( 33) minutes.
SMART Attributes Data Structure revision number: 1
Vendor Specific SMART Attributes with Thresholds:
ID# ATTRIBUTE_NAME FLAGS VALUE WORST THRESH FAIL RAW_VALUE
5 Reallocated_Sector_Ct PO--CK 100 100 010 - 0
9 Power_On_Hours -O--CK 099 099 000 - 36
12 Power_Cycle_Count -O--CK 099 099 000 - 7
177 Wear_Leveling_Count PO--C- 099 099 000 - 9
179 Used_Rsvd_Blk_Cnt_Tot PO--C- 100 100 010 - 0
181 Program_Fail_Cnt_Total -O--CK 100 100 010 - 0
182 Erase_Fail_Count_Total -O--CK 100 100 010 - 0
183 Runtime_Bad_Block PO--C- 100 100 010 - 0
187 Reported_Uncorrect -O--CK 100 100 000 - 0
190 Airflow_Temperature_Cel -O--CK 058 040 000 - 42
195 Hardware_ECC_Recovered -O-RC- 200 200 000 - 0
199 UDMA_CRC_Error_Count -OSRCK 253 253 000 - 0
235 Unknown_Attribute -O--C- 099 099 000 - 4
241 Total_LBAs_Written -O--CK 099 099 000 - 433352008
||||||_ K auto-keep
|||||__ C event count
||||___ R error rate
|||____ S speed/performance
||_____ O updated online
|______ P prefailure warning
General Purpose Log Directory Version 1
SMART Log Directory Version 1 [multi-sector log support]
GP/S Log at address 0x00 has 1 sectors [Log Directory]
GP/S Log at address 0x01 has 1 sectors [Summary SMART error log]
GP/S Log at address 0x02 has 2 sectors [Comprehensive SMART error log]
GP/S Log at address 0x03 has 2 sectors [Ext. Comprehensive SMART error log]
GP/S Log at address 0x06 has 1 sectors [SMART self-test log]
GP/S Log at address 0x07 has 2 sectors [Extended self-test log]
GP/S Log at address 0x09 has 1 sectors [Selective self-test log]
GP/S Log at address 0x10 has 1 sectors [NCQ Command Error]
GP/S Log at address 0x11 has 1 sectors [SATA Phy Event Counters]
GP/S Log at address 0x80 has 16 sectors [Host vendor specific log]
GP/S Log at address 0x81 has 16 sectors [Host vendor specific log]
GP/S Log at address 0x82 has 16 sectors [Host vendor specific log]
GP/S Log at address 0x83 has 16 sectors [Host vendor specific log]
(snip)
SMART Extended Comprehensive Error Log Version: 1 (2 sectors)
No Errors Logged
SMART Extended Self-test Log Version: 1 (2 sectors)
Num Test_Description Status Remaining LifeTime(hours) LBA_of_first_error
# 1 Short offline Completed without error 00% 27 -
# 2 Short offline Completed without error 00% 8 -
SMART Selective self-test log data structure revision number 1
SPAN MIN_LBA MAX_LBA CURRENT_TEST_STATUS
1 0 0 Not_testing
2 0 0 Not_testing
3 0 0 Not_testing
4 0 0 Not_testing
5 0 0 Not_testing
Selective self-test flags (0x0):
After scanning selected spans, do NOT read-scan remainder of disk.
If Selective self-test is pending on power-up, resume after 0 minute delay.
Warning: device does not support SCT Commands
SATA Phy Event Counters (GP Log 0x11)
ID Size Value Description
0x0001 2 0 Command failed due to ICRC error
0x0002 2 49152 R_ERR response for data FIS
0x0003 2 53248 R_ERR response for device-to-host data FIS
0x0004 2 57344 R_ERR response for host-to-device data FIS
0x0005 2 7952 R_ERR response for non-data FIS
0x0006 2 2562 R_ERR response for device-to-host non-data FIS
0x0007 2 4096 R_ERR response for host-to-device non-data FIS
0x0008 2 7952 Device-to-host non-data FIS retries
0x0009 2 7953 Transition from drive PhyRdy to drive PhyNRdy
0x000a 2 25 Device-to-host register FISes sent due to a COMRESET
0x000b 2 6145 CRC errors within host-to-device FIS
0x000d 2 7953 Non-CRC errors within host-to-device FIS
0x000f 2 8176 R_ERR response for host-to-device data FIS, CRC
0x0010 2 15 R_ERR response for host-to-device data FIS, non-CRC
0x0012 2 49153 R_ERR response for host-to-device non-data FIS, CRC
0x0013 2 12112 R_ERR response for host-to-device non-data FIS, non-CRC
--
"A mouse is a device used to point at the xterm you want to type in" - A.S.R.
Microsoft is to operating systems ....
.... what McDonalds is to gourmet cooking
Home page: http://marc.merlins.org/
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