On 3/3/20 10:42 AM, Greg Kroah-Hartman wrote:
> From: Coly Li <[email protected]>
>
> [ Upstream commit 0b96da639a4874311e9b5156405f69ef9fc3bef8 ]
>
> When run a cache set, all the bcache btree node of this cache set will
> be checked by bch_btree_check(). If the bcache btree is very large,
> iterating all the btree nodes will occupy too much system memory and
> the bcache registering process might be selected and killed by system
> OOM killer. kthread_run() will fail if current process has pending
> signal, therefore the kthread creating in run_cache_set() for gc and
> allocator kernel threads are very probably failed for a very large
> bcache btree.
>
> Indeed such OOM is safe and the registering process will exit after
> the registration done. Therefore this patch flushes pending signals
> during the cache set start up, specificly in bch_cache_allocator_start()
> and bch_gc_thread_start(), to make sure run_cache_set() won't fail for
> large cahced data set.
Please drop this one, it's being reverted in mainline.
--
Jens Axboe
On Tue, Mar 03, 2020 at 10:55:04AM -0700, Jens Axboe wrote:
> On 3/3/20 10:42 AM, Greg Kroah-Hartman wrote:
> > From: Coly Li <[email protected]>
> >
> > [ Upstream commit 0b96da639a4874311e9b5156405f69ef9fc3bef8 ]
> >
> > When run a cache set, all the bcache btree node of this cache set will
> > be checked by bch_btree_check(). If the bcache btree is very large,
> > iterating all the btree nodes will occupy too much system memory and
> > the bcache registering process might be selected and killed by system
> > OOM killer. kthread_run() will fail if current process has pending
> > signal, therefore the kthread creating in run_cache_set() for gc and
> > allocator kernel threads are very probably failed for a very large
> > bcache btree.
> >
> > Indeed such OOM is safe and the registering process will exit after
> > the registration done. Therefore this patch flushes pending signals
> > during the cache set start up, specificly in bch_cache_allocator_start()
> > and bch_gc_thread_start(), to make sure run_cache_set() won't fail for
> > large cahced data set.
>
> Please drop this one, it's being reverted in mainline.
Dropped from all trees now, thanks.
greg k-h
On 3/3/20 11:12 AM, Greg Kroah-Hartman wrote:
> On Tue, Mar 03, 2020 at 10:55:04AM -0700, Jens Axboe wrote:
>> On 3/3/20 10:42 AM, Greg Kroah-Hartman wrote:
>>> From: Coly Li <[email protected]>
>>>
>>> [ Upstream commit 0b96da639a4874311e9b5156405f69ef9fc3bef8 ]
>>>
>>> When run a cache set, all the bcache btree node of this cache set will
>>> be checked by bch_btree_check(). If the bcache btree is very large,
>>> iterating all the btree nodes will occupy too much system memory and
>>> the bcache registering process might be selected and killed by system
>>> OOM killer. kthread_run() will fail if current process has pending
>>> signal, therefore the kthread creating in run_cache_set() for gc and
>>> allocator kernel threads are very probably failed for a very large
>>> bcache btree.
>>>
>>> Indeed such OOM is safe and the registering process will exit after
>>> the registration done. Therefore this patch flushes pending signals
>>> during the cache set start up, specificly in bch_cache_allocator_start()
>>> and bch_gc_thread_start(), to make sure run_cache_set() won't fail for
>>> large cahced data set.
>>
>> Please drop this one, it's being reverted in mainline.
>
> Dropped from all trees now, thanks.
Thanks!
--
Jens Axboe