Messages in this thread |  | | From | Dieter Nützel <> | Subject | Re: Unresponiveness of 2.4.16 | Date | Wed, 28 Nov 2001 04:53:03 +0100 |
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Am Mittwoch, 28. November 2001 03:34 schrieb Mike Fedyk: > On Tue, Nov 27, 2001 at 06:13:41PM -0800, Andrew Morton wrote: > > Dieter N?tzel wrote: > > > Don't forget to tune max-readahead. > > > > Yes. Readahead is fairly critical and there may be additional fixes > > needed in this area. > > > > Someone recently added the /proc/sys/vm/max_readahead (?) tunable.
-mt (Marcelo Tosatti) our _new_ 2.4.x maintainer did it.
> Isn't this part of the max-readahead patch? > > Does /proc/sys/vm/max_readahead affect scsi in any way?
Hello people, can you read? I've reported U160 (SCSI) IBM DDYS (Ultrastar 36LZX) 18 GB 10k results...;-)
Kernel default: SunWave1 src/linux# cat /proc/sys/vm/min-readahead 3 SunWave1 src/linux# cat /proc/sys/vm/max-readahead 31 SunWave1 src/linux# hdparm -tT /dev/sda1 /dev/sda1: Timing buffer-cache reads: 128 MB in 0.80 seconds =160.00 MB/sec Timing buffered disk reads: 64 MB in 2.28 seconds = 28.07 MB/sec
SunWave1 src/linux# cat /proc/sys/vm/max-readahead 127 SunWave1 src/linux# hdparm -tT /dev/sda1 /dev/sda1: Timing buffer-cache reads: 128 MB in 0.80 seconds =160.00 MB/sec Timing buffered disk reads: 64 MB in 1.87 seconds = 34.22 MB/sec
So it improved hdparm by 0.5 MB at the inner and 6 MB at the outer cylinders.
max-readahead=31 max-readahead=127 26-28 MB/s 26.5-34 MB/s
max-readahead=63 is nearly the same max-readahead=255 little slower max-readahead=511 even little slower
Here is a snipped of the IBM specs:
Performance Data buffer 4 MB² Rotational speed 10,000 RPM Latency (average) 2.99 ms Media transfer rate 280-452 Mbits/sec Interface transfer rate 160 MB/sec Sustained data rate 21.7- 36.1MB/sec
Seek time Average 4.9 ms Track to track 0.5 ms Full track 10.5 ms
To Robert Love: I get the following in dmesg: lock-break-rml-2.4.16-1.patch
date: busy buffer lock_break: buffer.c:681: count was 2 not 551 invalidate: busy buffer lock_break: buffer.c:681: count was 2 not 551 invalidate: busy buffer [-]
lock-break-rml-2.4.16-2.patch
validate: busy buffer invalidate: busy buffer invalidate: busy buffer invalidate: busy buffer [-]
Now my dbench numbers. First without Noatun playing Ogg-Vorbis: dbench/dbench> time ./dbench 32 32 clients started ........................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................+................+..............................................................................+++.+.+.......+.....++++....++.....+++++.++++.++.+++++++******************************** Throughput 43.8254 MB/sec (NB=54.7818 MB/sec 438.254 MBit/sec) 14.490u 53.230s 1:37.40 69.5% 0+0k 0+0io 937pf+0w system load: 23.52
Second Noatun playing Ogg-Vorbis (with hiccup): dbench/dbench> time ./dbench 32 32 clients started ...............................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................+....+........................+.......++++...+.+...........+.+.....+++++.+.++..++..+++.++.++++.++******************************** Throughput 42.1212 MB/sec (NB=52.6515 MB/sec 421.212 MBit/sec) 14.710u 53.940s 1:41.29 67.7% 0+0k 0+0io 937pf+0w system load: 26.30
Not bad, I think. Andrew, your patch follows tomorrow.
Regards, Dieter - 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/
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