Hi,

is there a good reason to print the "database system is ready" message 
in StartupXLOG() in xact.c? It has a) nothing to do with xlog and b) 
opens a small race condition: the message gets printed, while it still 
take some CPU cycles until the postmaster really gets the SIGCHLD signal 
and sets StartupPID = 0. If you (or rather: an automated test program) 
try to connect within this timespan, you get a "database is starting up" 
error, which clearly contradicts the "is ready" message.

I admit this is not a real issue in the common case and only matters in 
automated testing or some such. But in case this does not break 
anything...  (ereport is used in the reaper, so I guess it's fine to use 
that in signal handlers). I'm not sure if the message is needed at all 
in BS_XLOG_BOOTSTRAP mode. Probably it should better say something 
different.

Patch attached.

Regards

Markus

Responses

• Re: [PATCHES] Fix "database is ready" race condition at 2007-02-04 19:15:18 from Tom Lane
• Re: Fix "database is ready" race condition at 2007-02-07 16:46:25 from Tom Lane

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