mirror_zfs/module
Matthew Ahrens dc303dcf5b
assertion failed in arc_wait_for_eviction()
If the system is very low on memory (specifically,
`arc_free_memory() < arc_sys_free/2`, i.e. less than 1/16th of RAM
free), `arc_evict_state_impl()` will defer wakups.  In this case, the
arc_evict_waiter_t's remain on the list, even though `arc_evict_count`
has been incremented past their `aew_count`.

The problem is that `arc_wait_for_eviction()` assumes that if there are
waiters on the list, the count they are waiting for has not yet been
reached.  However, the deferred wakeups may violate this, causing
`ASSERT(last->aew_count > arc_evict_count)` to fail.

This commit resolves the issue by having new waiters use the greater of
`arc_evict_count` and the last `aew_count`.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: George Wilson <gwilson@delphix.com>
Reviewed-by: George Amanakis <gamanakis@gmail.com>
Signed-off-by: Matthew Ahrens <mahrens@delphix.com>
Closes #11285
Closes #11397
2021-01-07 20:06:32 -08:00
..
avl Links in Source Files 2020-09-02 09:42:12 -07:00
icp Introduce CPU_SEQID_UNSTABLE 2020-11-02 11:51:12 -08:00
lua lua: avoid gcc -Wreturn-local-addr bug 2020-12-15 09:20:48 -08:00
nvpair Links in Source Files 2020-09-02 09:42:12 -07:00
os VZ 7 kernel compat: introduce ITER-enabled .direct_IO() via IOVECs 2020-12-30 14:18:29 -08:00
spl Cleanup linux module kbuild files 2020-06-10 09:24:15 -07:00
unicode Throw const on some strings 2020-10-02 17:44:10 -07:00
zcommon Linux 5.10 compat: use iov_iter in uio structure 2020-12-18 08:48:26 -08:00
zfs assertion failed in arc_wait_for_eviction() 2021-01-07 20:06:32 -08:00
zstd Optimize locking checks in mempool allocator 2020-11-02 12:10:07 -08:00
.gitignore Cleanup linux module kbuild files 2020-06-10 09:24:15 -07:00
Kbuild.in Add zstd support to zfs 2020-08-20 10:30:06 -07:00
Makefile.bsd FreeBSD: decouple ZFS_DEBUG from kernel debug settings 2020-11-24 09:16:46 -08:00
Makefile.in Fix Linux modules uninstall 2020-10-08 20:07:10 -07:00