On Thu, Dec 18, 2014 at 7:31 PM, Rahila Syed <rahilasyed90@gmail.com> wrote:
>>Isn't it better to allocate the memory for compression_scratch in
>>InitXLogInsert()
>>like hdr_scratch?
>
> I think making compression_scratch a statically allocated global variable
> is the result of following discussion earlier,
> http://www.postgresql.org/message-id/CA+TgmoazNBuwnLS4bpwyqgqteEznOAvy7KWdBm0A2-tBARn_aQ@mail.gmail.com
Yep, in this case the OS does not request this memory as long as it is
not touched, like when wal_compression is off all the time in the
backend. Robert mentioned that upthread.
--
Michael
