JIRA: https://issues.redhat.com/browse/RHEL-84906 Upstream Status: kernel/git/torvalds/linux.git commit a38425935f7886cef5fe04c796f36715e9d0ef3f Author: Mikulas Patocka <mpatocka@redhat.com> Date: Wed Jan 15 18:33:30 2025 +0100 dm-transaction-manager: use red-black trees instead of linear lists There was reported performance degradation when the shadow map contained too many entries [1]. The shadow map uses 256-bucket hash with linear lists - when there are too many entries, it has quadratic complexity. Meir Elisha proposed to add a module parameter that could configure the size of the hash array - however, this is not ideal because users don't know that they should increase the parameter when they get bad performance. This commit replaces the linear lists with rb-trees (so that there's a hash of rb-trees), they have logarithmic complexity, so it solves the performance degradation. Link: https://patchwork.kernel.org/project/dm-devel/patch/20241014134944.1264991-1-meir.elisha@volumez.com/ [1] Reported-by: Meir Elisha <meir.elisha@volumez.com> Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com> |
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.. | ||
Kconfig | ||
Makefile | ||
dm-array.c | ||
dm-array.h | ||
dm-bitset.c | ||
dm-bitset.h | ||
dm-block-manager.c | ||
dm-block-manager.h | ||
dm-btree-internal.h | ||
dm-btree-remove.c | ||
dm-btree-spine.c | ||
dm-btree.c | ||
dm-btree.h | ||
dm-persistent-data-internal.h | ||
dm-space-map-common.c | ||
dm-space-map-common.h | ||
dm-space-map-disk.c | ||
dm-space-map-disk.h | ||
dm-space-map-metadata.c | ||
dm-space-map-metadata.h | ||
dm-space-map.h | ||
dm-transaction-manager.c | ||
dm-transaction-manager.h |