Hi Coly
Thanks for you comments.
> Hi Junhui,
>
> This method is complicated IMHO.
The main idea of this patch is:
GC thread
allocator thread
==>triggered by sectors_to_gc
set ca->prepare_gc to GC_PREPARING
to notify allocator thread to
prepare for GC ==>detect
ca->prepare_gc is
GC_PREPARING, fill the
go to invalidate_buckets(),
==>waiting for allocator and fill free_inc queue
with
thread to prepare over reclaimable buckets,
after
that, set ca->prepare_gc to
GC_PREPARED to notify GC
thread being prepared OK
==>detect ca->prepare_gc is
prepared OK, set
ca->prepare_gc back to
GC_PREPARE_NONE, and continue GC
> Why not in bch_allocator_thread()
> simple call wake_up_gc(ca->set) after invalidate_buckets() ?
In this patch, GC is triggered by sectors_to_gc, and I/Os from front side
continue exist, so we notify allocator to pack the free_inc queue
full of buckets before GC, then we could have enough buckets for front side
I/Os during GC period.
Maybe the code is somewhat redundant, I will try to refactoring the code
in the next patch.
Thanks.
Tang Junhui
