Messages in this thread |  | | Date | Tue, 23 Jan 2001 00:11:55 +0100 | | From | Jens Axboe <> | | Subject | Re: 2.4.1pre8 slowdown on dbench tests |
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On Mon, Jan 22 2001, Marcelo Tosatti wrote: > > Jens, > > Steven is a seeing a slowdown in his results, too. > > > On Mon, 22 Jan 2001, Steven Cole wrote: > > > On Thursday 18 January 2001 14:49, Marcelo Tosatti wrote: > > > > > Steven, > > > > > > The issue is the difference between pre4 and pre8. > > > > > > Could you please try pre4 and report results ? > > > > > > Thanks > > > > Ok, here are the results for 2.4.1-pre4, along with the original -pre8 > > results. There does appear to be a slowdown. > > > > 2.4.1-pre4 > > average: 9.77876 MB/sec > > > > Throughput 10.3677 MB/sec (NB=12.9597 MB/sec 103.677 MBit/sec) > > Throughput 9.61291 MB/sec (NB=12.0161 MB/sec 96.1291 MBit/sec) > > Throughput 9.92944 MB/sec (NB=12.4118 MB/sec 99.2944 MBit/sec) > > Throughput 9.20502 MB/sec (NB=11.5063 MB/sec 92.0502 MBit/sec) > > > > 2.4.1-pre8: > > Average 9.25707 MB/sec > > > > Throughput 8.93444 MB/sec (NB=11.1681 MB/sec 89.3444 MBit/sec) > > Throughput 9.43609 MB/sec (NB=11.7951 MB/sec 94.3609 MBit/sec) > > Throughput 9.5075 MB/sec (NB=11.8844 MB/sec 95.075 MBit/sec) > > Throughput 9.15026 MB/sec (NB=11.4378 MB/sec 91.5026 MBit/sec) > > > > This was done on a dual P-III, 256MB machine.
Stephen,
To rule out other factors, could you try 2.4.1-pre8 with blk_started_io() and blk_finished_io() defined to nothing in include/linux/blkdev.h? This will disable the max-locked-buffers heuristic.
Also, are the numbers above consistent for repeated runs (with boots in between)?
-- * Jens Axboe <axboe@suse.de> * SuSE Labs - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org Please read the FAQ at http://www.tux.org/lkml/
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