Messages in this thread Patch in this message | | | Date | Tue, 17 Jul 2007 14:35:58 -0700 | From | Ethan Solomita <> | Subject | [PATCH 4/6] cpuset write vmscan |
| |
Direct reclaim: cpuset aware writeout
During direct reclaim we traverse down a zonelist and are carefully checking each zone if its a member of the active cpuset. But then we call pdflush without enforcing the same restrictions. In a larger system this may have the effect of a massive amount of pages being dirtied and then either
A. No writeout occurs because global dirty limits have not been reached
or
B. Writeout starts randomly for some dirty inode in the system. Pdflush may just write out data for nodes in another cpuset and miss doing proper dirty handling for the current cpuset.
In both cases dirty pages in the zones of interest may not be affected and writeout may not occur as necessary.
Fix that by restricting pdflush to the active cpuset. Writeout will occur from direct reclaim the same way as without a cpuset.
Signed-off-by: Christoph Lameter <clameter@sgi.com> Acked-by: Ethan Solomita <solo@google.com>
---
Patch against 2.6.22-rc6-mm1
diff -uprN -X 0/Documentation/dontdiff 3/mm/vmscan.c 4/mm/vmscan.c --- 3/mm/vmscan.c 2007-07-11 21:16:14.000000000 -0700 +++ 4/mm/vmscan.c 2007-07-11 21:16:26.000000000 -0700 @@ -1183,7 +1183,8 @@ unsigned long try_to_free_pages(struct z */ if (total_scanned > sc.swap_cluster_max + sc.swap_cluster_max / 2) { - wakeup_pdflush(laptop_mode ? 0 : total_scanned, NULL); + wakeup_pdflush(laptop_mode ? 0 : total_scanned, + &cpuset_current_mems_allowed); sc.may_writepage = 1; } - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |