Is TRIM working with gmirror?

[Miroslav Lachman]

Jia-Shiun Li wrote:
> On Thu, Jan 9, 2014 at 6:04 AM, Miroslav Lachman<000.fbsd at quip.cz>  wrote:
>> Steven Hartland wrote:
>> It is production server, so I can't play with it and try 10.x, but we are
>> running some other servers on 9.2, so if 9.2 gmirror has support for TRIM, I
>> can upgrade this server to 9.2.
>
> According to release notes, gmirror TRIM is supported since 9.1R.
>
> I did a little test on 9.2R livecd environment with commands you
> stated in previous mail. Both amd64&  i386 work. 2 md devices were
> used as backend device, but it should not differ since gmirror reports
> 'candelete' attribute regardless of backend capability.
>
> The above seem to conflict with your result on 9.2 test machines.
> Could you confirm that? Maybe there's something missing.

The machine with SSD disks and TRIM on gmirror is running FreeBSD 8.4, 
not 9.2.
It is strange anyway, because 8.4R is 6 month newer than 9.1R and has 
many improvements over 9.1R (for example ZFS feature flags).
So if 9.1R has support for TRIM in gmirror, it can be expected in 8.4 too.

Thank you for detailed explanation. I will try upgrade to 9.2 soon.

Miroslav Lachman