linux 3.1 issue: bdi dirty threshold goes mad
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Quoted 6 lines · Wu Fengguang
Hi,
FYI, I find bdi dirty threshold madness in the newly released v3.1 according to the gray lines in the attached graphs, which are for these test cases:
Quoted 7 lines
3G-UKEY-HDD/ext4-1dd-4k-8p-2948M-20:10-3.1.0-vanilla+ 3G-UKEY-HDD/xfs-10dd-4k-8p-2948M-20:10-3.1.0-vanilla+ 3G-UKEY-HDD/xfs-1dd-4k-8p-2948M-20:10-3.1.0-vanilla+
It's basically doing concurrent dd's to a USB key and a hard disk.
Don't know what's going wrong, but at least should be bisectable..
It seems to depend on kernel builds: the problem disappears in the newly compiled kernels. This makes it pretty hard to catch the root cause...
Thanks,
Fengguang