Re: [HACKERS] Speed up Clog Access by increasing CLOG buffers

Robert Haas wrote:

> The smoking gun was in 009_twophase_slave.log:
> 
> TRAP: FailedAssertion("!(nsubxids == MyPgXact->nxids)", File:
> "clog.c", Line: 288)
> 
> ...and then the node shuts down, which is why this hangs forever.
> (Also... what's up with it hanging forever instead of timing out or
> failing or something?)

This bit my while messing with 2PC tests recently.  I think it'd be
worth doing something about this, such as causing the test to die if we
request a server to (re)start and it doesn't start or it immediately
crashes.  This doesn't solve the problem of a server crashing at a point
not immediately after start, though.

(It'd be very annoying to have to sprinkle the Perl test code with
"assert $server->islive", but perhaps we can add assertions of some kind
in PostgresNode itself).

-- 
Álvaro Herrera                https://www.2ndQuadrant.com/
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