Re: Online verification of checksums

From: Fabien COELHO <coelho(at)cri(dot)ensmp(dot)fr>
To: Michael Banck <michael(dot)banck(at)credativ(dot)de>
Cc: David Steele <david(at)pgmasters(dot)net>, Stephen Frost <sfrost(at)snowman(dot)net>, PostgreSQL Hackers <pgsql-hackers(at)lists(dot)postgresql(dot)org>, Tomas Vondra <tomas(dot)vondra(at)2ndquadrant(dot)com>
Subject: Re: Online verification of checksums
Date: 2018-09-26 11:23:44
Message-ID: alpine.DEB.2.21.1809191738070.901@lancre
Views: Raw Message | Whole Thread | Download mbox | Resend email
Lists: 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

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

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

+ if (block_retry == false)

Why not trust boolean operations?

if (!block_retry)


In response to


Browse pgsql-hackers by date

  From Date Subject
Next Message Peter Eisentraut 2018-09-26 11:36:05 Re: Implementing SQL ASSERTION
Previous Message Fabien COELHO 2018-09-26 11:20:49 Re: pgbench - add pseudo-random permutation function