On Tue, Feb 01 2005, Catalin(ux aka Dino) BOIE wrote:Hello!
I have a weird problem with a server. I use deadline. The output of vmstat is: 1 1 12312 6064 7580 815432 0 0 5332 456 1263 3119 22 5 0 73 0 1 12312 5280 7584 816240 0 0 6204 620 1307 1530 15 4 0 81 0 1 12312 6096 7528 815088 0 0 7604 8732 1256 1398 5 8 0 87 0 1 12312 6048 7528 815144 0 0 8 8 1243 1440 14 2 0 84 0 1 12312 6048 7528 815168 0 0 0 0 1261 1287 8 2 0 90 0 2 12312 6040 7584 815184 0 0 0 0 1258 1197 7 2 0 91 0 2 12312 6024 7584 815208 0 0 0 0 1265 1309 6 5 0 89 0 2 12312 6024 7584 815208 0 0 0 136 1253 365 2 2 0 96 0 2 12312 5984 7584 815208 0 0 0 0 1268 413 2 1 0 97 0 2 12312 6052 7584 815208 0 0 0 0 1270 375 2 1 0 97 1 0 12312 6164 7584 815156 0 0 6188 288 1270 4314 23 5 0 72 0 1 12312 5684 7536 815592 0 0 4128 8656 1270 1316 14 3 0 83 0 1 12312 5684 7536 815608 0 0 0 0 1258 1251 8 3 0 89 0 1 12312 5552 7536 815628 0 0 0 0 1258 1327 8 2 0 90 0 1 12312 5552 7536 815644 0 0 0 0 1264 1127 7 2 0 91 0 1 12312 5552 7536 815668 0 0 0 2 1258 1225 8 3 0 89 0 3 12312 5248 7588 816108 0 0 4340 585 1249 1316 7 3 0 90 0 2 12312 5612 7584 815680 0 0 3092 188 1254 411 3 1 0 96 0 2 12312 5564 7584 815676 0 0 0 0 1261 259 2 2 0 96 0 2 12312 5564 7584 815676 0 0 0 0 1254 348 2 1 0 97
It seems strange because iowait is at 90% but nothing is trasnfered to/from disk. Why is that?
The bi/bo numbers are sometimes a little confusing, it doesn't mean that the drive is actually doing 8656kb of io at that very second - only that this much io was queued to the drive.
I run postgresql on this server and I'm not satistied by it's speed.
Single Pentium IV, IDE disk.
What can be the problem?
Do you have write cache enabled on the drive?
No. Intentionaly I disabled it:
ATA device, with non-removable media
Model Number: WDC WD800JB-00CRA1
Serial Number: WD-WMA8E8797395
Firmware Revision: 17.07W17
Standards:
Supported: 5 4 3 2
Likely used: 6
Configuration:
Logical max current
cylinders 16383 16383
heads 16 16
sectors/track 63 63
--
CHS current addressable sectors: 16514064
LBA user addressable sectors: 156301488
device size with M = 1024*1024: 76319 MBytes
device size with M = 1000*1000: 80026 MBytes (80 GB)
Capabilities:
LBA, IORDY(can be disabled)
bytes avail on r/w long: 40 Queue depth: 1
Standby timer values: spec'd by Standard, with device specific minimum
R/W multiple sector transfer: Max = 16 Current = 16
Recommended acoustic management value: 128, current value: 254
DMA: mdma0 mdma1 mdma2 udma0 udma1 udma2 udma3 udma4 *udma5
Cycle time: min=120ns recommended=120ns
PIO: pio0 pio1 pio2 pio3 pio4
Cycle time: no flow control=120ns IORDY flow control=120ns
Commands/features:
Enabled Supported:
* READ BUFFER cmd
* WRITE BUFFER cmd
* Host Protected Area feature set
* Look-ahead
Write cache
* Power Management feature set
Security Mode feature set
* SMART feature set
* Device Configuration Overlay feature set
Automatic Acoustic Management feature set
SET MAX security extension
* DOWNLOAD MICROCODE cmd
* SMART self-test
* SMART error logging
Security:
supported
not enabled
not locked
frozen
not expired: security count
not supported: enhanced erase
HW reset results:
CBLID- above Vih
Device num = 0 determined by CSEL
Checksum: correct
Thanks!
-- Jens Axboe
--- Catalin(ux aka Dino) BOIE catab at deuroconsult.ro http://kernel.umbrella.ro/ - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
