REVIEW: Track TRUNCATE via pgstat

https://commitfest.postgresql.org/action/patch_view?id=1661 (apologies for not replying to the thread; I can't find it in my inbox)

Patch applies and passes make check. Code formatting looks good.

The regression test partially tests this. It does not cover 2PC, nor does it test rolling back a subtransaction that contains a truncate. The latter actually doesn't work correctly.

The test also adds 2.5 seconds of forced pg_sleep. I think that's both bad and unnecessary. When I removed the sleeps I still saw times of less than 0.1 seconds. Also, wait_for_trunc_test_stats() should display something if it times out; otherwise you'll have a test failure and won't have any indication why.

I've attached a patch that adds logging on timeout and contains a test case that demonstrates the rollback to savepoint bug.
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Jim Nasby, Data Architect, Blue Treble Consulting
Data in Trouble? Get it in Treble! http://BlueTreble.com