ZFS how to find out if ZIL is currently enabled?

[Andriy Gapon]

on 28/07/2011 15:48 Ivan Voras said the following:
> On 28 July 2011 14:24, Andriy Gapon <avg at freebsd.org> wrote:
>> on 28/07/2011 14:32 Ivan Voras said the following:
>>> Grepping for "zil" in sysctls doesn't give anything useful:
>>>
>>> # sysctl -a | grep zil
>>> vfs.zfs.zil_replay_disable: 0
>>>
>>> (its description is "Disable intent logging replay" so it looks like a
>>> crash recovery option)
>>>
>>> ... so is there a way to find out if ZIL is enabled?
>>>
>>> I can look at kenv but for some reason I can't trust its value right now.
>>
>> Here is a hammer: kgdb.
>> But perhaps there is a more suitable tool :)
> 
> Hmmm, no, it looks like the zil_disable code is missing in the latest
> 8-stable! This confirmes what I noticed in operation and why I didn't
> trust kenv.
> 
>>From the various csup dates I have on the servers it looks like it's
> been removed somewhere between April and now, possibly with ZFS 28
> MFC?

http://www.mail-archive.com/freebsd-stable@freebsd.org/msg114251.html

> I.e. this code is missing:
> 
> *:/sys> grep -rn zil_disable *
> cddl/contrib/opensolaris/uts/common/fs/zfs/sys/zil.h:382:extern int zil_disable;
> cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_vfsops.c:897:    if
> (zil_disable) {
> cddl/contrib/opensolaris/uts/common/fs/zfs/zil.c:69:int zil_disable =
> 0;        /* disable intent logging */
> cddl/contrib/opensolaris/uts/common/fs/zfs/zil.c:71:TUNABLE_INT("vfs.zfs.zil_disable",
> &zil_disable);
> cddl/contrib/opensolaris/uts/common/fs/zfs/zil.c:72:SYSCTL_INT(_vfs_zfs,
> OID_AUTO, zil_disable, CTLFLAG_RW, &zil_disable, 0,
> cddl/contrib/opensolaris/uts/common/fs/zfs/zvol.c:450:          if
> (bp->bio_cmd == BIO_FLUSH && !zil_disable)
> 
> Any ideas?


-- 
Andriy Gapon