I have observed that in a dump/restore scenario the longest time is spent on index creation for larger tables, I have a suggestion of how the performance could be improved thus reducing the time to recover from a crash. Not sure if this is possible but would definitely be a nice addition to the TODO list.

1) Add a new config paramter e.g work_maintanence_max_mem this will the max memory postgresql *can* claim if need be.

2) During the dump phase of the DB postgresql estimates the "work_maintenance_mem" that would be required to create the index in memory(if possible) and add's a
SET work_maintenance_mem="the value calculated" (IF this value is less than work_maintanence_max_mem. )

3) During the restore phase the appropriate memory is allocated in RAM and the index creation takes less time since PG does not have to sort on disk.

Adi Alurkar (DBA sf.NET) <[EMAIL PROTECTED]>
1024D/79730470 A491 5724 74DE 956D 06CB  D844 6DF1 B972 7973 0470

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