Manfred Spraul wrote:
Gaetano Mendola wrote:
a1) If exist check that is a 16MB file ( the request can ~ arrive during the copy ),
I think this will fail under windows: "copy" first sets the file size and then transfers the data. I wouldn't rule out that some Unices use the same implementation.
I'm doing this work as "proof of concept", after made it working on my platform we can even write them in C.
~ a2) If the file not exist this mean that is not yet recycled and
~ is a partial file present on the partial directory,
~ check if the "alive" file is older then 2 minutes.
~ a21) If the file is older than 2 minutes I assume that
~ the master is dead:
I'd concentrate on cold failover: the user (or the OS) must call a script to cause a fail-over. The tricky thing are the various partial connection losses between master and spare: perhaps the alive file is not updated anymore due to a net split, but the master is still alive. Unless you are really careful both master and spare could run.
I agree but as I said I'm doing it as "proof of concept", we can even change later the way to discovery that master is dead.
I'm facing however to the following problems:
1) Discovery the actual WAL file
I'm supposing is the last modified file inside the
pg_xlog directory. If this is not the good method
may I know how I can know it ?2) During the recovery phase postmaster ask me for file that will never be
there like: 00000001.history.
Actualy if the file does not exist and contain the string history
instead to wait for him I exit with 1 exit codeIs this right for you ?
Regards Gaetano Mendola
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