On Fri, Jan 11, 2019 at 9:20 PM Tomas Vondra <tomas.von...@2ndquadrant.com> wrote:
> > > > On 1/11/19 7:40 PM, Robert Haas wrote: > > On Fri, Jan 11, 2019 at 5:21 AM Magnus Hagander <mag...@hagander.net> > wrote: > >> Would it make sense to add a column to pg_stat_database showing > >> the total number of checksum errors that have occurred in a database? > >> > >> It's really a ">1 means it's bad", but it's a lot easier to monitor > >> that in the statistics views, and given how much a lot of people > >> set their systems out to log, it's far too easy to miss individual > >> checksum matches in the logs. > >> > >> If we track it at the database level, I don't think the overhead > >> of adding one more counter would be very high either. > > > > It's probably not the idea way to track it. If you have a terabyte or > > fifty of data, and you see that you have some checksum failures, good > > luck finding the offending blocks. > > > > Isn't that somewhat similar to deadlocks, which we also track in > pg_stat_database? The number of deadlocks is rather useless on it's own, > you need to dive into the server log to find the details. Same for > checksum errors. > It is a bit similar yeah. Though a checksum counter is really a "you need to look at fixing this right away" in a bit more sense than deadlocks. But yes, the fact that we already tracks deadlocks there is a good example. (Of course, I believe I added that one at some point as well, so I'm clearly biased there) > But I'm tentatively in favor of your proposal anyway, because it's > > pretty simple and cheap and might help people, and doing something > > noticeably better is probably annoyingly complicated. > > > > +1 > Yeah, that's the idea behind it -- it's cheap, and an early-warning-indicator. -- Magnus Hagander Me: https://www.hagander.net/ <http://www.hagander.net/> Work: https://www.redpill-linpro.com/ <http://www.redpill-linpro.com/>
