[Comm] io perfomance tuning

[Alex Murygin]

День добрый.

Идет раздача контента по nfs на 10 машин.
Сервер debian/unstable с nfs-kernel-server и ext3. Raid-5 на 3ware 8506 
(10 Serial ATA).
Клиенты freebsd 4.10.

Отчего такой высокий %util при таком низком rsec/s? Что можно почитать 
по этому поводу?

$ uname -a
Linux dedicated 2.4.25-1-386 #2 Wed Apr 14 19:38:08 EST 2004 i686 
GNU/Linux


$ iostat -dkx 10
....
Device:    rrqm/s wrqm/s   r/s   w/s  rsec/s  wsec/s    rkB/s    wkB/s avgrq-sz avgqu-sz   await  svctm  %util
scsi/host0/bus0/target0/lun0/disc
           213.09  71.49 29.69  3.12 1942.19  592.04   971.10   296.02    77.25     0.00    0.76   0.42   1.38
....
scsi/host0/bus0/target0/lun0/disc
           238.30   1.30 77.60  0.60 2527.20   15.20  1263.60     7.60    32.51     0.56    7.20   5.59  43.70
....
scsi/host0/bus0/target0/lun0/disc
           148.80   0.70  5.00  0.90 1230.40   12.80   615.20     6.40   210.71     0.93  158.14 138.64  81.80
....


$ tw_cli 
3ware CLI> info c0
Controller: c0
-------------
Driver:   1.02.00.037
Model:    8506-12
FW:       FE7S 1.05.00.065
BIOS:     BE7X 1.08.00.048
Monitor:  ME7X 1.01.00.038
Serial #: F17800A4090020
PCB:      Rev5
PCHIP:    1.30-66
ACHIP:    3.20


# of units: 2
        Unit 0: RAID 5 1.67 TB ( 3584655360 blocks): OK
        Unit 10: SPARE 189.92 GB ( 398295040 blocks): OK

# of ports: 12
        Port 0: Maxtor 6Y200M0 Y631TXME 189.92 GB (398297088 blocks): OK(unit 0)
        Port 1: Maxtor 6Y200M0 Y631TX5E 189.92 GB (398297088 blocks): OK(unit 0)
        Port 2: Maxtor 6Y200M0 Y631VJVE 189.92 GB (398297088 blocks): OK(unit 0)
        Port 3: Maxtor 6Y200M0 Y631TZRE 189.92 GB (398297088 blocks): OK(unit 0)
        Port 4: Maxtor 6Y200M0 Y631V01E 189.92 GB (398297088 blocks): OK(unit 0)
        Port 5: Maxtor 6Y200M0 Y631C6EE 189.92 GB (398297088 blocks): OK(unit 0)
        Port 6: Maxtor 6Y200M0 Y631VLCE 189.92 GB (398297088 blocks): OK(unit 0)
        Port 7: Maxtor 6Y200M0 Y630VKSE 189.92 GB (398297088 blocks): OK(unit 0)
        Port 8: Maxtor 6Y200M0 Y631VKWE 189.92 GB (398297088 blocks): OK(unit 0)
        Port 9: Maxtor 6Y200M0 Y631TYHE 189.92 GB (398297088 blocks): OK(unit 0)
        Port 10: Maxtor 6Y200M0 Y631XG2E 189.92 GB (398297088 blocks): OK(unit 10)


Спасибо
-- 
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- Alex Murygin, AITOC -
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