> So we also need a "txg dirty" or similar
> property to be exposed from the kernel.
Or not..
if you find this condition, defer, but check again in a minute (really, after a
full txg_interval has passed) rather than on the next scheduled snapshot.
on that next check, if the txg has advanced aga
> you missed my point: you can't compare the current
> txg to an old cr_txg directly, since the current
> txg value will be at least 1 higher, even if
> no changes have been made.
OIC. So we also need a "txg dirty" or similar property to be exposed from the
kernel.
--
This message posted from op
Daniel Carosone writes:
>> you can fetch the "cr_txg" (cr for creation) for a
>> snapshot using zdb,
>
> yes, but this is hardly an appropriate interface.
agreed.
> zdb is also likely to cause disk activity because it looks at many
> things other than the specific item in question.
I'd expect
> you can fetch the "cr_txg" (cr for creation) for a
> snapshot using zdb,
yes, but this is hardly an appropriate interface. zdb is also likely to cause
disk activity because it looks at many things other than the specific item in
question.
> but the very creation of a snapshot requires a new
>
Daniel Carosone writes:
>> I don't think it is easy to do, the txg counter is on
>> a pool level,
>> [..]
>> it would help when the entire pool is idle, though.
>
> .. which is exactly the scenario in question: when the disks are
> likely to be spun down already (or to spin down soon without furt
Andrew Gabriel wrote:
Kjetil Torgrim Homme wrote:
Daniel Carosone writes:
Would there be a way to avoid taking snapshots if they're going to be
zero-sized?
I don't think it is easy to do, the txg counter is on a pool level,
AFAIK:
# zdb -u spool
Uberblock
magic = 00bab
Kjetil Torgrim Homme wrote:
Daniel Carosone writes:
Would there be a way to avoid taking snapshots if they're going to be
zero-sized?
I don't think it is easy to do, the txg counter is on a pool level,
AFAIK:
# zdb -u spool
Uberblock
magic = 00bab10c
version = 1
> Daniel Carosone writes:
>
> > Would there be a way to avoid taking snapshots if
> > they're going to be zero-sized?
>
> I don't think it is easy to do, the txg counter is on
> a pool level,
> [..]
> it would help when the entire pool is idle, though.
.. which is exactly the scenario in questi
Daniel Carosone writes:
> Would there be a way to avoid taking snapshots if they're going to be
> zero-sized?
I don't think it is easy to do, the txg counter is on a pool level,
AFAIK:
# zdb -u spool
Uberblock
magic = 00bab10c
version = 13
txg = 1773324
