Btrfs: allow shrink_delalloc flush the needed reclaimed pages (877da174) · Commits · 戴 / test

Currently we only allow a maximum of 2 megabytes of pages to be flushed at a time. This was ok before, but now we have overcommit which will screw us in a heartbeat if we are quickly filling the disk. So instead pick either 2 megabytes or the number of pages we need to reclaim to be safe again, which ever is larger. Thanks, Signed-off-by:

Josef Bacik <josef@redhat.com>

fs/btrfs/extent-tree.c

+3 −2

Original line number	Diff line number	Diff line
		@@ -3343,7 +3343,7 @@ static int shrink_delalloc(struct btrfs_trans_handle *trans,
		u64 max_reclaim;
		u64 reclaimed = 0;
		long time_left;
		int nr_pages = (2 * 1024 * 1024) >> PAGE_CACHE_SHIFT;
		unsigned long nr_pages = (2 * 1024 * 1024) >> PAGE_CACHE_SHIFT;
		int loops = 0;
		unsigned long progress;

		@@ -3366,7 +3366,8 @@ static int shrink_delalloc(struct btrfs_trans_handle *trans,
		}

		max_reclaim = min(reserved, to_reclaim);

		nr_pages = max_t(unsigned long, nr_pages,
		max_reclaim >> PAGE_CACHE_SHIFT);
		while (loops < 1024) {
		/* have the flusher threads jump in and do some IO */
		smp_mb();

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