Revision c4f675cd40d955d539180506c09515c90169b15b authored by Sergei Trofimovich on 20 May 2011, 20:20:30 UTC, committed by Chris Mason on 23 May 2011, 17:24:14 UTC
Observed as a large delay when --mixed filesystem is filled up.
Test example:
1. create tiny --mixed FS:
$ dd if=/dev/zero of=2G.img seek=$((2048 * 1024 * 1024 - 1)) count=1 bs=1
$ mkfs.btrfs --mixed 2G.img
$ mount -oloop 2G.img /mnt/ut/
2. Try to fill it up:
$ dd if=/dev/urandom of=10M.file bs=10240 count=1024
$ seq 1 256 | while read file_no; do echo $file_no; time cp 10M.file ${file_no}.copy; done
Up to '200.copy' it goes fast, but when disk fills-up each -ENOSPC
message takes 3 seconds to pop-up _every_ ENOSPC (and in usermode linux
it's even more: 30-60 seconds!). (Maybe, time depends on kernel's timer resolution).
No IO, no CPU load, just rescheduling. Some debugging revealed busy spinning
in shrink_delalloc.
Signed-off-by: Sergei Trofimovich <slyfox@gentoo.org>
Reviewed-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
1 parent 0f3b708
| File | Mode | Size |
|---|---|---|
| Kconfig | -rw-r--r-- | 3.0 KB |
| Kconfig.iosched | -rw-r--r-- | 1.8 KB |
| Makefile | -rw-r--r-- | 641 bytes |
| blk-cgroup.c | -rw-r--r-- | 39.1 KB |
| blk-cgroup.h | -rw-r--r-- | 10.8 KB |
| blk-core.c | -rw-r--r-- | 73.6 KB |
| blk-exec.c | -rw-r--r-- | 2.8 KB |
| blk-flush.c | -rw-r--r-- | 12.5 KB |
| blk-integrity.c | -rw-r--r-- | 11.4 KB |
| blk-ioc.c | -rw-r--r-- | 3.6 KB |
| blk-iopoll.c | -rw-r--r-- | 5.9 KB |
| blk-lib.c | -rw-r--r-- | 4.3 KB |
| blk-map.c | -rw-r--r-- | 8.2 KB |
| blk-merge.c | -rw-r--r-- | 11.1 KB |
| blk-settings.c | -rw-r--r-- | 25.1 KB |
| blk-softirq.c | -rw-r--r-- | 4.1 KB |
| blk-sysfs.c | -rw-r--r-- | 14.3 KB |
| blk-tag.c | -rw-r--r-- | 9.9 KB |
| blk-throttle.c | -rw-r--r-- | 28.5 KB |
| blk-timeout.c | -rw-r--r-- | 5.6 KB |
| blk.h | -rw-r--r-- | 4.5 KB |
| bsg.c | -rw-r--r-- | 23.7 KB |
| cfq-iosched.c | -rw-r--r-- | 104.6 KB |
| cfq.h | -rw-r--r-- | 3.7 KB |
| compat_ioctl.c | -rw-r--r-- | 21.0 KB |
| deadline-iosched.c | -rw-r--r-- | 11.2 KB |
| elevator.c | -rw-r--r-- | 24.6 KB |
| genhd.c | -rw-r--r-- | 42.4 KB |
| ioctl.c | -rw-r--r-- | 8.1 KB |
| noop-iosched.c | -rw-r--r-- | 2.4 KB |
| scsi_ioctl.c | -rw-r--r-- | 18.3 KB |
Computing file changes ...
