>switching from 2.4.7-ac3 to -ac4, disk access seems to be much more
>synchronis. running a ./configure script causes all kinds of trashing, as
>does installing .debs. i'm using reiserfs on top of software raid 0 on an
>alpha.
I can second that on 2.4.7-ac4 - ac9 (all versions).
Dbench show a dramatic decrease in disk troughput (~10 MB/sec) for every case
I've tested. I have a ReiserFS only system and the test partition was /opt
(/dev/sda8) with ~2.7 GB stuff on it, so we have some aging, too. It is the
last and slowest partition on my fast IBM U160 18 GB, 10.000 RPMs disk.
I've used 2.4.7 + acX + transaction-tracking-2 (Chris) + use-once-pages
(Daniel).
Now, some numbers (it should be noted that the u+s times are mostly equal but
the whole time and the throughput is different.
first lines for 2.4.7-ac3, then 2.4.7-ac9
dbench 48
Throughput 27.3983 MB/sec (NB=34.2479 MB/sec 273.983 MBit/sec)
37.580u 115.730s 3:51.30 66.2% 0+0k 0+0io 1310pf+0w
Throughput 18.4711 MB/sec (NB=23.0889 MB/sec 184.711 MBit/sec)
37.710u 121.900s 5:43.05 46.5% 0+0k 0+0io 1311pf+0w
dbench 32
Throughput 34.7552 MB/sec (NB=43.444 MB/sec 347.552 MBit/sec)
24.620u 73.980s 2:02.55 80.4% 0+0k 0+0io 911pf+0w
Throughput 21.8827 MB/sec (NB=27.3533 MB/sec 218.827 MBit/sec)
25.410u 76.610s 3:14.04 52.5% 0+0k 0+0io 912pf+0w
dbench 16
16 clients started
Throughput 37.7379 MB/sec (NB=47.1724 MB/sec 377.379 MBit/sec)
12.350u 35.330s 0:56.97 83.6% 0+0k 0+0io 511pf+0w
Throughput 30.0396 MB/sec (NB=37.5495 MB/sec 300.396 MBit/sec)
12.970u 37.320s 1:10.31 71.5% 0+0k 0+0io 511pf+0w
dbench 8
Throughput 40.9394 MB/sec (NB=51.1742 MB/sec 409.394 MBit/sec)
6.080u 17.420s 0:26.80 87.6% 0+0k 0+0io 311pf+0w
Throughput 28.174 MB/sec (NB=35.2175 MB/sec 281.74 MBit/sec)
6.280u 18.360s 0:38.49 64.0% 0+0k 0+0io 312pf+0w
dbench 4
Throughput 41.4035 MB/sec (NB=51.7544 MB/sec 414.035 MBit/sec)
3.140u 8.240s 0:13.76 82.7% 0+0k 0+0io 211pf+0w
Throughput 25.2641 MB/sec (NB=31.5801 MB/sec 252.641 MBit/sec)
3.270u 8.680s 0:21.91 54.5% 0+0k 0+0io 212pf+0w
dbench 2
Throughput 38.6387 MB/sec (NB=48.2983 MB/sec 386.387 MBit/sec)
1.680u 4.030s 0:07.83 72.9% 0+0k 0+0io 161pf+0w
Throughput 30.4352 MB/sec (NB=38.0441 MB/sec 304.352 MBit/sec)
1.690u 4.300s 0:09.68 61.8% 0+0k 0+0io 162pf+0w
dbench 1
Throughput 33.3689 MB/sec (NB=41.7111 MB/sec 333.689 MBit/sec)
0.820u 2.000s 0:04.96 56.8% 0+0k 0+0io 136pf+0w
Throughput 30.8583 MB/sec (NB=38.5729 MB/sec 308.583 MBit/sec)
0.750u 2.010s 0:05.28 52.2% 0+0k 0+0io 137pf+0w
System spec:
Athlon 550 I (yes, the first generation)
MSI MS-6167 Rev 1.0B (AMD Irongate C4, without bypass)
640 MB Pc100-2-2-2 SDRAM
SCSI subsystem driver Revision: 1.00
scsi0 : Adaptec AIC7XXX EISA/VLB/PCI SCSI HBA DRIVER, Rev 6.2.1
<Adaptec 2940 Ultra SCSI adapter>
aic7880: Ultra Wide Channel A, SCSI Id=7, 16/255 SCBs
Vendor: IBM Model: DDYS-T18350N Rev: S96H
Type: Direct-Access ANSI SCSI revision: 03
Vendor: IBM Model: DDRS-34560D Rev: DC1B
Type: Direct-Access ANSI SCSI revision: 02
Vendor: IBM Model: DDRS-34560W Rev: S71D
Type: Direct-Access ANSI SCSI revision: 02
Filesystem 1k-blocks Used Available Use% Mounted on
/dev/sda3 104412 69616 34796 67% /
/dev/sda2 1518088 37392 1480696 3% /tmp
/dev/sda5 1028092 334056 694036 33% /var
/dev/sda6 2048188 87188 1961000 5% /home
/dev/sda7 5124536 1752784 3371752 35% /usr
/dev/sda8 7068348 2715860 4352488 39% /opt
tmpfs 321188 0 321188 0% /dev/shm
Could it be that the ReiserFS cleanups in ac4 do harm?
http://marc.theaimsgroup.com/?l=reiserfs&m=99683332027428&w=2
Thanks,
Dieter
-- Dieter Nützel Graduate Student, Computer ScienceUniversity of Hamburg Department of Computer Science Cognitive Systems Group Vogt-Kölln-Straße 30 D-22527 Hamburg, Germany
email: nuetzel@kogs.informatik.uni-hamburg.de @home: Dieter.Nuetzel@hamburg.de - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/