Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
gfs2: less aggressive low-memory log flushing
It turns out that for some workloads, the fix in commit b74cd55aa9a9d
("gfs2: low-memory forced flush fixes") causes the number of forced log
flushes to increase to a degree that the overall filesystem performance
drops significantly. Address that by forcing a log flush only when
gfs2_writepages cannot make any progress rather than when it cannot make
"enough" progress.
Fixes: b74cd55aa9a9d ("gfs2: low-memory forced flush fixes")
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
+3
-2
+3
-2
fs/gfs2/aops.c
+3
-2
fs/gfs2/aops.c
···
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struct writeback_control *wbc)
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{
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struct gfs2_sbd *sdp = gfs2_mapping2sbd(mapping);
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long initial_nr_to_write = wbc->nr_to_write;
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struct iomap_writepage_ctx wpc = {
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.inode = mapping->host,
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.wbc = wbc,
···
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int ret;
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/*
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-
* Even if we didn't write enough pages here, we might still be holding
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+
* Even if we didn't write any pages here, we might still be holding
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* dirty pages in the ail. We forcibly flush the ail because we don't
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* want balance_dirty_pages() to loop indefinitely trying to write out
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* pages held in the ail that it can't find.
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*/
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ret = iomap_writepages(&wpc);
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if (ret == 0 && wbc->nr_to_write > 0)
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if (ret == 0 && wbc->nr_to_write == initial_nr_to_write)
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set_bit(SDF_FORCE_AIL_FLUSH, &sdp->sd_flags);
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return ret;
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}