On Thu, May 11, 2000 at 12:23:19AM -0700, Linus Torvalds wrote:
> Hmm..
>
> Having tested some more, the "wait for locked buffer" logic in
> fs/buffer.c (sync_page_buffers()) seems toserialize thingsawhole lote more
> than I initially thought..
>
> Does it act the way you expect if you change the
>
> if (buffer_locked(p))
> __wait_on_buffer(p);
> else if (buffer_dirty(p))
> ll_rw_block(..
>
> to a simpler
>
> if (buffer_dirty(p) && !buffer_locked(p))
> ll_rw_block(..
>
> which doesn't endup serializing the IO all the time?
A little bit better! 203 vmstat-line-seconds before, now 155
vmstat-line-seconds to complete. It seems to be doing a better job like
this, but still doesn't write out in blocks like it used to:
2.3.99pre7-9 vanilla:
0 1 1 32 2212 216 112424 0 4 609 527 239 112 5 8 87
0 1 1 32 3004 216 111472 0 4 608 540 327 120 5 7 87
0 1 1 32 3008 232 111252 0 4 768 1083 405 252 3 11 86
0 1 1 32 1964 240 112144 0 0 594 570 422 222 3 14 83
1 1 1 60 2932 248 111164 0 36 661 586 349 226 3 13 84
2.3.99pre7-9 with above adjustment:
0 1 1 64 3032 272 110768 0 0 833 628 414 338 5 28 67
0 1 1 64 2608 276 111040 0 0 769 1081 440 268 3 24 72
0 1 1 64 2684 284 110804 0 0 847 1089 370 280 6 12 82
0 1 0 64 2832 276 110796 0 0 706 558 384 193 7 11 82
0 1 1 136 1280 284 112440 0 72 911 1084 494 251 6 13 81
Also, it's still not as fast as classzone-27 writing out, and CPU use is
still a bit higher:
2.3.99pre7-8 classzone-27:
0 1 0 540 2852 272 110796 0 0 1089 1000 465 148 7 5 88
0 1 0 540 2980 264 110676 0 0 1423 1500 380 140 7 7 86
0 1 0 540 2584 272 111068 0 0 1059 1000 421 146 9 3 88
0 1 0 988 2556 276 111524 0 448 1473 1612 523 148 10 6 84
1 0 0 988 2704 264 111408 0 0 1135 1000 423 163 6 6 88
(All from random areas, sorry... it might be a good idea to read all of
the output in the attachment.)
I attached vmstat-3.txt, the full output with "2.3.99pre7-9 with above
adjustment".
Simon-
[ Stormix Technologies Inc. ][ NetNation Communications Inc. ]
[ sim@stormix.com ][ sim@netnation.com ]
[ Opinions expressed are not necessarily those of my employers. ]
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This archive was generated by hypermail 2b29 : Mon May 15 2000 - 21:00:18 EST