|
The system:
MB: Supermicro P6SBU (Adaptec 7890 on
board)
CPU: 1 pentium III 500 MHz Mem: 256Mb 1x9.1Gb IBM DNES-309170W disk on fast/se
channel
4x18.2Gb IBM DNES-318350W on ultra2 channel The 18.2 Gb disks are in raid0 software. Below the /etc/raidtab file: raiddev
/dev/md0
raid-level 0 nr-raid-disks 4 persistent-superblock 1 chunk-size 128 device /dev/sdb1 raid-disk 0 device /dev/sdc1 raid-disk 1 device /dev/sdd1 raid-disk 2 device /dev/sde1 raid-disk 3 output of dmesg related to scsi conf (in
2.4.0-test4 boot):
md.c: sizeof(mdp_super_t) = 4096
(scsi0) <Adaptec AIC-7890/1 Ultra2 SCSI host adapter> found at PCI 0/14/0 (scsi0) Wide Channel, SCSI ID=7, 32/255 SCBs (scsi0) Downloading sequencer code... 392 instructions downloaded scsi0 : Adaptec AHA274x/284x/294x (EISA/VLB/PCI-Fast SCSI) 5.2.1/5.2.0 <Adaptec AIC-7890/1 Ultra2 SCSI host adapter> scsi : 1 host. (scsi0:0:5:0) Synchronous at 10.0 Mbyte/sec, offset 15. Vendor: SONY Model: SDT-9000 Rev: 0400 Type: Sequential-Access ANSI SCSI revision: 02 (scsi0:0:6:0) Synchronous at 40.0 Mbyte/sec, offset 31. Vendor: IBM Model: DNES-309170W Rev: SA30 Type: Direct-Access ANSI SCSI revision: 03 Detected scsi disk sda at scsi0, channel 0, id 6, lun 0 (scsi0:0:8:0) Synchronous at 80.0 Mbyte/sec, offset 31. Vendor: IBM Model: DNES-318350W Rev: SA30 Type: Direct-Access ANSI SCSI revision: 03 Detected scsi disk sdb at scsi0, channel 0, id 8, lun 0 (scsi0:0:9:0) Synchronous at 80.0 Mbyte/sec, offset 31. Vendor: IBM Model: DNES-318350W Rev: SA30 Type: Direct-Access ANSI SCSI revision: 03 Detected scsi disk sdc at scsi0, channel 0, id 9, lun 0 (scsi0:0:10:0) Synchronous at 80.0 Mbyte/sec, offset 31. Vendor: IBM Model: DNES-318350W Rev: SA30 Type: Direct-Access ANSI SCSI revision: 03 Detected scsi disk sdd at scsi0, channel 0, id 10, lun 0 (scsi0:0:12:0) Synchronous at 80.0 Mbyte/sec, offset 31. Vendor: IBM Model: DNES-318350W Rev: SA30 Type: Direct-Access ANSI SCSI revision: 03 Detected scsi disk sde at scsi0, channel 0, id 12, lun 0 scsi : detected 5 SCSI disks total. SCSI device sda: hdwr sector= 512 bytes. Sectors= 17916240 [8748 MB] [8.7 GB] Partition check: sda: sda1 sda2 < sda5 sda6 sda7 > SCSI device sdb: hdwr sector= 512 bytes. Sectors= 35843670 [17501 MB] [17.5 GB] sdb: sdb1 SCSI device sdc: hdwr sector= 512 bytes. Sectors= 35843670 [17501 MB] [17.5 GB] sdc: sdc1 SCSI device sdd: hdwr sector= 512 bytes. Sectors= 35843670 [17501 MB] [17.5 GB] sdd: sdd1 SCSI device sde: hdwr sector= 512 bytes. Sectors= 35843670 [17501 MB] [17.5 GB] sde: sde1 [snipped]
(read) sdb1's sb offset: 17920384 [events:
00000085]
(read) sdc1's sb offset: 17920384 [events: 00000085] (read) sdd1's sb offset: 17920384 [events: 00000085] (read) sde1's sb offset: 17920384 [events: 00000085] autorun ... considering sde1 ... adding sde1 ... adding sdd1 ... adding sdc1 ... adding sdb1 ... created md0 bind<sdb1,1> bind<sdc1,2> bind<sdd1,3> bind<sde1,4> running: <sde1><sdd1><sdc1><sdb1> now! sde1's event counter: 00000085 sdd1's event counter: 00000085 sdc1's event counter: 00000085 sdb1's event counter: 00000085 raid0 personality registered md0: max total readahead window set to 2048k md0: 4 data-disks, max readahead per data-disk: 512k raid0: looking at sdb1 raid0: comparing sdb1(17920384) with sdb1(17920384) raid0: END raid0: ==> UNIQUE raid0: 1 zones raid0: looking at sdc1 raid0: comparing sdc1(17920384) with sdb1(17920384) raid0: EQUAL raid0: looking at sdd1 raid0: comparing sdd1(17920384) with sdb1(17920384) raid0: EQUAL raid0: looking at sde1 raid0: comparing sde1(17920384) with sdb1(17920384) raid0: EQUAL raid0: FINAL 1 zones zone 0 checking sdb1 ... contained as device 0 (17920384) is smallest!. checking sdc1 ... contained as device 1 checking sdd1 ... contained as device 2 checking sde1 ... contained as device 3 zone->nb_dev: 4, size: 71681536 current zone offset: 17920384 done. raid0 : md_size is 71681536 blocks. raid0 : conf->smallest->size is 71681536 blocks. raid0 : nb_zone is 1. raid0 : Allocating 8 bytes for hash. md: updating md0 RAID superblock on device sde1 [events: 00000086](write) sde1's sb offset: 17920384 sdd1 [events: 00000086](write) sdd1's sb offset: 17920384 sdc1 [events: 00000086](write) sdc1's sb offset: 17920384 sdb1 [events: 00000086](write) sdb1's sb offset: 17920384 . ... autorun DONE. Detected scsi tape st0 at scsi0, channel 0, id 5, lun 0 st: bufsize 32768, wrt 30720, max init. buffers 4, s/g segs 16. These are the outputs of bonnie++ version 1.00 compiled on 2.2.14 kernel ( redhat 6.2) kernel 2.2.14 no tagged Version 1.00 ------Sequential Output------ --Sequential Input- --Random- -Per Chr- --Block-- -Rewrite- -Per Chr- --Block-- --Seeks-- Machine MB K/sec %CP K/sec %CP K/sec %CP K/sec %CP K/sec %CP /sec %CP Unknown 1000 8400 97 56908 70 21380 48 8475 96 58199 44 nan -21474836 48 ------Sequential Create------ --------Random Create-------- -Create-- --Read--- -Delete-- -Create-- --Read--- -Delete-- files /sec %CP /sec %CP /sec %CP /sec %CP /sec %CP /sec %CP 30 175 96 627 99 6451 99 182 99 806 99 722 91 Unknown,1000,8400,97,56908,70,21380,48,8475,96,58199,44, nan,-2147483648,30,175,96,62 7,99,6451,99,182,99,806,99,722,91 kernel 2.4.0-test4 no tagged
Version 1.00 ------Sequential Output------ --Sequential Input- --Random- -Per Chr- --Block-- -Rewrite- -Per Chr- --Block-- --Seeks-- Machine MB K/sec %CP K/sec %CP K/sec %CP K/sec %CP K/sec %CP /sec %CP Unknown 1000 8249 97 51642 37 10498 18 6190 72 17248 19 nan -2147483648 ------Sequential Create------ --------Random Create-------- -Create-- --Read--- -Delete-- -Create-- --Read--- -Delete-- files /sec %CP /sec %CP /sec %CP /sec %CP /sec %CP /sec %CP 30 174 99 +++++ 93 9417 93 180 99 +++++ 104 1282 98 Unknown,1000,8249,97,51642,37,10498,18,6190,72,17248,19, nan,-2147483648,30,174,99,+++++,93,9417,93,180,99,+++++,104,1282,98 What about them? In particular the big difference
between rewrite seq. output (21380 48 % cpu in 2.2 vs 10498
18%
in 2.4) and block seq. input
(58199 44% in 2.2 vs 17248 19% in 2.4)?
Making dd or cp of big files the performances of
2.4 remains 1/3 respect of 2.2.14 (due to seq. input bad
performance??),
eg. 62 secs for 512MB dd with 1MB block size versus
23 secs in 2.2.14). The cpu load is 45% in 2.2 versus 18% in 2.4.
The problem with kswapd overload seems not to be so present analyzing vmstat, but the performance gap remains. Is philosophical (logical) change toward multi user/multi processor environment or bad performance? Thanks in advance for your clarifications. Gianluca PS: tell me if I can be of any help for testing conditions with my hardware. |
