diff options
Diffstat (limited to 'meta/recipes-kernel/lttng/lttng-modules/0004-fix-ext4-limit-the-length-of-per-inode-prealloc-list.patch')
| -rw-r--r-- | meta/recipes-kernel/lttng/lttng-modules/0004-fix-ext4-limit-the-length-of-per-inode-prealloc-list.patch | 84 |
1 files changed, 84 insertions, 0 deletions
diff --git a/meta/recipes-kernel/lttng/lttng-modules/0004-fix-ext4-limit-the-length-of-per-inode-prealloc-list.patch b/meta/recipes-kernel/lttng/lttng-modules/0004-fix-ext4-limit-the-length-of-per-inode-prealloc-list.patch new file mode 100644 index 0000000000..e29c07252c --- /dev/null +++ b/meta/recipes-kernel/lttng/lttng-modules/0004-fix-ext4-limit-the-length-of-per-inode-prealloc-list.patch @@ -0,0 +1,84 @@ +From 8fe742807e65af29dac3fea568ff93cbc5dd9a56 Mon Sep 17 00:00:00 2001 +From: Michael Jeanson <mjeanson@efficios.com> +Date: Mon, 24 Aug 2020 15:26:04 -0400 +Subject: [PATCH 04/10] fix: ext4: limit the length of per-inode prealloc list + (v5.9) +MIME-Version: 1.0 +Content-Type: text/plain; charset=UTF-8 +Content-Transfer-Encoding: 8bit + +See upstream commit: + + commit 27bc446e2def38db3244a6eb4bb1d6312936610a + Author: brookxu <brookxu.cn@gmail.com> + Date: Mon Aug 17 15:36:15 2020 +0800 + + ext4: limit the length of per-inode prealloc list + + In the scenario of writing sparse files, the per-inode prealloc list may + be very long, resulting in high overhead for ext4_mb_use_preallocated(). + To circumvent this problem, we limit the maximum length of per-inode + prealloc list to 512 and allow users to modify it. + + After patching, we observed that the sys ratio of cpu has dropped, and + the system throughput has increased significantly. We created a process + to write the sparse file, and the running time of the process on the + fixed kernel was significantly reduced, as follows: + + Running time on unfixed kernel： + [root@TENCENT64 ~]# time taskset 0x01 ./sparse /data1/sparce.dat + real 0m2.051s + user 0m0.008s + sys 0m2.026s + + Running time on fixed kernel： + [root@TENCENT64 ~]# time taskset 0x01 ./sparse /data1/sparce.dat + real 0m0.471s + user 0m0.004s + sys 0m0.395s + +Upstream-Status: Backport + +Signed-off-by: Michael Jeanson <mjeanson@efficios.com> +Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> +Change-Id: I5169cb24853d4da32e2862a6626f1f058689b053 +--- + instrumentation/events/lttng-module/ext4.h | 15 +++++++++++++++ + 1 file changed, 15 insertions(+) + +diff --git a/instrumentation/events/lttng-module/ext4.h b/instrumentation/events/lttng-module/ext4.h +index 5f7ab28..72ad4c9 100644 +--- a/instrumentation/events/lttng-module/ext4.h ++++ b/instrumentation/events/lttng-module/ext4.h +@@ -460,6 +460,20 @@ LTTNG_TRACEPOINT_EVENT(ext4_mb_release_group_pa, + ) + #endif + ++#if (LINUX_VERSION_CODE >= KERNEL_VERSION(5,9,0)) ++LTTNG_TRACEPOINT_EVENT(ext4_discard_preallocations, ++ TP_PROTO(struct inode *inode, unsigned int len, unsigned int needed), ++ ++ TP_ARGS(inode, len, needed), ++ ++ TP_FIELDS( ++ ctf_integer(dev_t, dev, inode->i_sb->s_dev) ++ ctf_integer(ino_t, ino, inode->i_ino) ++ ctf_integer(unsigned int, len, len) ++ ctf_integer(unsigned int, needed, needed) ++ ) ++) ++#else + LTTNG_TRACEPOINT_EVENT(ext4_discard_preallocations, + TP_PROTO(struct inode *inode), + +@@ -470,6 +484,7 @@ LTTNG_TRACEPOINT_EVENT(ext4_discard_preallocations, + ctf_integer(ino_t, ino, inode->i_ino) + ) + ) ++#endif + + LTTNG_TRACEPOINT_EVENT(ext4_mb_discard_preallocations, + TP_PROTO(struct super_block *sb, int needed), +-- +2.19.1 + |