Re: Proposed patch to change TOAST compression strategy

"Tom Lane" <tgl@sss.pgh.pa.us> writes:

> * Adds an early-failure path to the compressor as suggested by Jan:
> if it's been unable to find even one compressible substring in the
> first 1KB (parameterizable), assume we're looking at incompressible
> input and give up.  (There are various ways this could be done, but
> this way seems to add the least overhead to the compressor's inner
> loop.)

I'm not sure how to test the rest of it, but this bit seems testable. I fear
this may be too conservative. Even nigh incompressible data will find a few
backreferences.

I'll try some tests and see.

--
  Gregory Stark
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