Re: Patch: Write Amplification Reduction Method (WARM)

On Thu, Mar 30, 2017 at 10:08 AM, Amit Kapila <amit.kapila16@gmail.com> wrote:
> I think we should not consider doing compression and decompression as
> free at this point in code, because we hold a buffer lock during
> recheck. Buffer locks are meant for short-term locks (it is even
> mentioned in storage/buffer/README), doing all the
> compression/decompression/detoast stuff under these locks doesn't
> sound advisable to me.  It can block many concurrent operations.

Compression and decompression might cause performance problems, but
try to access the TOAST table would be fatal; that probably would have
deadlock hazards among other problems.

-- 
Robert Haas
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