Re: Online verification of checksums - Mailing list pgsql-hackers

From Fabien COELHO
Subject Re: Online verification of checksums
Date
Msg-id alpine.DEB.2.21.1809191738070.901@lancre
Whole thread Raw
In response to Re: Online verification of checksums  (Michael Banck <michael.banck@credativ.de>)
Responses Re: Online verification of checksums  (Michael Banck <michael.banck@credativ.de>)
List pgsql-hackers
Hallo Michael,

Patch v3 applies cleanly, code compiles and make check is ok, but the 
command is probably not tested anywhere, as already mentioned on other 
threads.

The patch is missing a documentation update.

There are debatable changes of behavior:

    if (errno == ENOENT) return / continue...

For instance, a file disappearing is ok online, but not so if offline. On 
the other hand, the probability that a file suddenly disappears while the 
server offline looks remote, so reporting such issues does not seem 
useful.

However I'm more wary with other continues/skips added. ISTM that skipping 
a block because of a read error, or because it is new, or some other 
reasons, is not the same thing, so should be counted & reported 
differently?

   + if (block_retry == false)

Why not trust boolean operations?

   if (!block_retry)

-- 
Fabien.


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