Re: [RFC][PATCH 1/2] nfs: writeback pages wait queue
From: Wu Fengguang
Date: Wed Oct 19 2011 - 23:59:34 EST
> @@ -424,6 +419,10 @@ int nfs_writepages(struct address_space
> err = write_cache_pages(mapping, wbc, nfs_writepages_callback, &pgio);
> nfs_pageio_complete(&pgio);
>
> + nfs_wait_congested(wbc->sync_mode == WB_SYNC_ALL,
> + &nfss->backing_dev_info,
> + nfss->writeback_wait);
> +
> clear_bit_unlock(NFS_INO_FLUSHING, bitlock);
> smp_mb__after_clear_bit();
> wake_up_bit(bitlock, NFS_INO_FLUSHING);
The "wakeup NFS_INO_FLUSHING after congestion wait" logic looks
strange, so I tried moving the nfs_wait_congested() _after_
wake_up_bit()...and got write_bw regressions.
OK, not knowing what's going on underneath, I'll just stick to the current form.
3.1.0-rc9-ioless-full-nfs-ino-flushing-next-20111014+ 3.1.0-rc9-ioless-full-nfs-wakeup-wait-next-20111014+
------------------------ ------------------------
417.26 -5.5% 394.24 TOTAL write_bw
5179.00 -12.6% 4529.00 TOTAL nfs_nr_commits
340466.00 -37.2% 213939.00 TOTAL nfs_nr_writes
722.54 +17.6% 849.42 TOTAL nfs_commit_size
3.75 +6.3% 3.99 TOTAL nfs_write_size
15477.38 -14.5% 13235.34 TOTAL nfs_write_queue_time
517.54 +13.0% 585.00 TOTAL nfs_write_rtt_time
16011.09 -13.5% 13848.09 TOTAL nfs_write_execute_time
714.65 -43.4% 404.65 TOTAL nfs_commit_queue_time
12787.93 +9.2% 13960.35 TOTAL nfs_commit_rtt_time
13519.94 +6.4% 14387.44 TOTAL nfs_commit_execute_time
3.1.0-rc9-ioless-full-nfs-ino-flushing-next-20111014+ 3.1.0-rc9-ioless-full-nfs-wakeup-wait-next-20111014+
------------------------ ------------------------
44.42 -0.8% 44.05 NFS-thresh=100M/nfs-10dd-4k-32p-32768M-100M:10-X
78.49 -8.0% 72.22 NFS-thresh=100M/nfs-1dd-4k-32p-32768M-100M:10-X
69.96 -2.4% 68.30 NFS-thresh=100M/nfs-2dd-4k-32p-32768M-100M:10-X
70.59 -3.8% 67.88 NFS-thresh=1G/nfs-10dd-4k-32p-32768M-1024M:10-X
76.76 -8.7% 70.09 NFS-thresh=1G/nfs-1dd-4k-32p-32768M-1024M:10-X
77.04 -6.9% 71.70 NFS-thresh=1G/nfs-2dd-4k-32p-32768M-1024M:10-X
417.26 -5.5% 394.24 TOTAL write_bw
3.1.0-rc9-ioless-full-nfs-ino-flushing-next-20111014+ 3.1.0-rc9-ioless-full-nfs-wakeup-wait-next-20111014+
------------------------ ------------------------
2683.00 -1.8% 2634.00 NFS-thresh=100M/nfs-10dd-4k-32p-32768M-100M:10-X
811.00 -43.8% 456.00 NFS-thresh=100M/nfs-1dd-4k-32p-32768M-100M:10-X
1049.00 -16.7% 874.00 NFS-thresh=100M/nfs-2dd-4k-32p-32768M-100M:10-X
474.00 -8.4% 434.00 NFS-thresh=1G/nfs-10dd-4k-32p-32768M-1024M:10-X
56.00 -23.2% 43.00 NFS-thresh=1G/nfs-1dd-4k-32p-32768M-1024M:10-X
106.00 -17.0% 88.00 NFS-thresh=1G/nfs-2dd-4k-32p-32768M-1024M:10-X
5179.00 -12.6% 4529.00 TOTAL nfs_nr_commits
3.1.0-rc9-ioless-full-nfs-ino-flushing-next-20111014+ 3.1.0-rc9-ioless-full-nfs-wakeup-wait-next-20111014+
------------------------ ------------------------
17641.00 -2.2% 17257.00 NFS-thresh=100M/nfs-10dd-4k-32p-32768M-100M:10-X
177296.00 -54.1% 81335.00 NFS-thresh=100M/nfs-1dd-4k-32p-32768M-100M:10-X
26346.00 +41.6% 37309.00 NFS-thresh=100M/nfs-2dd-4k-32p-32768M-100M:10-X
22279.00 +12.7% 25107.00 NFS-thresh=1G/nfs-10dd-4k-32p-32768M-1024M:10-X
67612.00 -59.7% 27271.00 NFS-thresh=1G/nfs-1dd-4k-32p-32768M-1024M:10-X
29292.00 -12.4% 25660.00 NFS-thresh=1G/nfs-2dd-4k-32p-32768M-1024M:10-X
340466.00 -37.2% 213939.00 TOTAL nfs_nr_writes
3.1.0-rc9-ioless-full-nfs-ino-flushing-next-20111014+ 3.1.0-rc9-ioless-full-nfs-wakeup-wait-next-20111014+
------------------------ ------------------------
4.97 +1.1% 5.03 NFS-thresh=100M/nfs-10dd-4k-32p-32768M-100M:10-X
29.00 +63.5% 47.43 NFS-thresh=100M/nfs-1dd-4k-32p-32768M-100M:10-X
19.99 +17.0% 23.40 NFS-thresh=100M/nfs-2dd-4k-32p-32768M-100M:10-X
44.66 +5.3% 47.03 NFS-thresh=1G/nfs-10dd-4k-32p-32768M-1024M:10-X
408.94 +18.6% 485.03 NFS-thresh=1G/nfs-1dd-4k-32p-32768M-1024M:10-X
214.96 +12.3% 241.50 NFS-thresh=1G/nfs-2dd-4k-32p-32768M-1024M:10-X
722.54 +17.6% 849.42 TOTAL nfs_commit_size
3.1.0-rc9-ioless-full-nfs-ino-flushing-next-20111014+ 3.1.0-rc9-ioless-full-nfs-wakeup-wait-next-20111014+
------------------------ ------------------------
0.76 +1.5% 0.77 NFS-thresh=100M/nfs-10dd-4k-32p-32768M-100M:10-X
0.13 +100.4% 0.27 NFS-thresh=100M/nfs-1dd-4k-32p-32768M-100M:10-X
0.80 -31.1% 0.55 NFS-thresh=100M/nfs-2dd-4k-32p-32768M-100M:10-X
0.95 -14.4% 0.81 NFS-thresh=1G/nfs-10dd-4k-32p-32768M-1024M:10-X
0.34 +125.8% 0.76 NFS-thresh=1G/nfs-1dd-4k-32p-32768M-1024M:10-X
0.78 +6.5% 0.83 NFS-thresh=1G/nfs-2dd-4k-32p-32768M-1024M:10-X
3.75 +6.3% 3.99 TOTAL nfs_write_size
3.1.0-rc9-ioless-full-nfs-ino-flushing-next-20111014+ 3.1.0-rc9-ioless-full-nfs-wakeup-wait-next-20111014+
------------------------ ------------------------
460.14 -29.9% 322.63 NFS-thresh=100M/nfs-10dd-4k-32p-32768M-100M:10-X
718.69 +68.2% 1208.67 NFS-thresh=100M/nfs-1dd-4k-32p-32768M-100M:10-X
5203.60 -26.1% 3843.39 NFS-thresh=100M/nfs-2dd-4k-32p-32768M-100M:10-X
427.40 +93.4% 826.64 NFS-thresh=1G/nfs-10dd-4k-32p-32768M-1024M:10-X
7369.68 -18.0% 6041.98 NFS-thresh=1G/nfs-1dd-4k-32p-32768M-1024M:10-X
1297.87 -23.6% 992.02 NFS-thresh=1G/nfs-2dd-4k-32p-32768M-1024M:10-X
15477.38 -14.5% 13235.34 TOTAL nfs_write_queue_time
3.1.0-rc9-ioless-full-nfs-ino-flushing-next-20111014+ 3.1.0-rc9-ioless-full-nfs-wakeup-wait-next-20111014+
------------------------ ------------------------
134.58 -8.9% 122.60 NFS-thresh=100M/nfs-10dd-4k-32p-32768M-100M:10-X
33.24 +48.8% 49.46 NFS-thresh=100M/nfs-1dd-4k-32p-32768M-100M:10-X
89.69 -19.4% 72.31 NFS-thresh=100M/nfs-2dd-4k-32p-32768M-100M:10-X
129.86 -35.3% 84.03 NFS-thresh=1G/nfs-10dd-4k-32p-32768M-1024M:10-X
48.33 +239.4% 164.05 NFS-thresh=1G/nfs-1dd-4k-32p-32768M-1024M:10-X
81.84 +13.1% 92.55 NFS-thresh=1G/nfs-2dd-4k-32p-32768M-1024M:10-X
517.54 +13.0% 585.00 TOTAL nfs_write_rtt_time
3.1.0-rc9-ioless-full-nfs-ino-flushing-next-20111014+ 3.1.0-rc9-ioless-full-nfs-wakeup-wait-next-20111014+
------------------------ ------------------------
595.23 -25.1% 445.75 NFS-thresh=100M/nfs-10dd-4k-32p-32768M-100M:10-X
753.68 +67.4% 1261.46 NFS-thresh=100M/nfs-1dd-4k-32p-32768M-100M:10-X
5294.55 -26.0% 3917.11 NFS-thresh=100M/nfs-2dd-4k-32p-32768M-100M:10-X
559.44 +63.1% 912.46 NFS-thresh=1G/nfs-10dd-4k-32p-32768M-1024M:10-X
7424.41 -16.2% 6221.64 NFS-thresh=1G/nfs-1dd-4k-32p-32768M-1024M:10-X
1383.78 -21.3% 1089.67 NFS-thresh=1G/nfs-2dd-4k-32p-32768M-1024M:10-X
16011.09 -13.5% 13848.09 TOTAL nfs_write_execute_time
3.1.0-rc9-ioless-full-nfs-ino-flushing-next-20111014+ 3.1.0-rc9-ioless-full-nfs-wakeup-wait-next-20111014+
------------------------ ------------------------
2.34 +2.5% 2.40 NFS-thresh=100M/nfs-10dd-4k-32p-32768M-100M:10-X
1.59 +488.4% 9.37 NFS-thresh=100M/nfs-1dd-4k-32p-32768M-100M:10-X
2.63 +47.0% 3.86 NFS-thresh=100M/nfs-2dd-4k-32p-32768M-100M:10-X
68.22 -6.5% 63.78 NFS-thresh=1G/nfs-10dd-4k-32p-32768M-1024M:10-X
618.34 -52.9% 291.44 NFS-thresh=1G/nfs-1dd-4k-32p-32768M-1024M:10-X
21.54 +56.9% 33.80 NFS-thresh=1G/nfs-2dd-4k-32p-32768M-1024M:10-X
714.65 -43.4% 404.65 TOTAL nfs_commit_queue_time
3.1.0-rc9-ioless-full-nfs-ino-flushing-next-20111014+ 3.1.0-rc9-ioless-full-nfs-wakeup-wait-next-20111014+
------------------------ ------------------------
766.76 +1.7% 779.63 NFS-thresh=100M/nfs-10dd-4k-32p-32768M-100M:10-X
344.34 +49.3% 514.10 NFS-thresh=100M/nfs-1dd-4k-32p-32768M-100M:10-X
431.90 +15.0% 496.81 NFS-thresh=100M/nfs-2dd-4k-32p-32768M-100M:10-X
3743.78 +5.6% 3954.60 NFS-thresh=1G/nfs-10dd-4k-32p-32768M-1024M:10-X
3699.59 +14.0% 4216.05 NFS-thresh=1G/nfs-1dd-4k-32p-32768M-1024M:10-X
3801.55 +5.2% 3999.17 NFS-thresh=1G/nfs-2dd-4k-32p-32768M-1024M:10-X
12787.93 +9.2% 13960.35 TOTAL nfs_commit_rtt_time
3.1.0-rc9-ioless-full-nfs-ino-flushing-next-20111014+ 3.1.0-rc9-ioless-full-nfs-wakeup-wait-next-20111014+
------------------------ ------------------------
769.38 +1.7% 782.27 NFS-thresh=100M/nfs-10dd-4k-32p-32768M-100M:10-X
346.06 +51.3% 523.52 NFS-thresh=100M/nfs-1dd-4k-32p-32768M-100M:10-X
434.96 +15.2% 501.07 NFS-thresh=100M/nfs-2dd-4k-32p-32768M-100M:10-X
3813.17 +5.4% 4020.45 NFS-thresh=1G/nfs-10dd-4k-32p-32768M-1024M:10-X
4318.75 +4.4% 4507.51 NFS-thresh=1G/nfs-1dd-4k-32p-32768M-1024M:10-X
3837.62 +5.6% 4052.61 NFS-thresh=1G/nfs-2dd-4k-32p-32768M-1024M:10-X
13519.94 +6.4% 14387.44 TOTAL nfs_commit_execute_time
Thanks,
Fengguang
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