On 01/31/2018 09:51 PM, Jan Wieck wrote: > > > On Wed, Jan 31, 2018 at 12:32 PM, Stefan Blanke > <stefan.blanke@xxxxxxxxxxxxxx <mailto:stefan.blanke@xxxxxxxxxxxxxx>> wrote: > > > > > I'll bet you it's not that. It's quite unlikely that would fail with > > exactly 1GB request size. It seems much more like a buffer that we keep > > to be power of 2. The question is which one. > > I had dismissed corruption before writing in. It's exactly 1GB every > time this has happened - and we can dump the full dataset > periodically without issue. > > >> I have my money on a corrupted TOAST entry. Is this happening on > >> trustworthy hardware or beige box with no ECC or RAID? > > It's good quality commercial hardware in our colo - no exactly sure > what. > > > If it is a sporadic issue and you can dump the full dataset, then I just > lost my money (Tomas, you coming to PGConf in Jersey City?). > Unfortunately no, but I'm sure there will be other opportunities to buy me a beer ;-) Like pgcon, for example. > > But then, if this is a plain COPY to stdout ... I am wondering what > could possibly be in that path that wants to allocate 1GB. Or is this > not so plain but rather a COPY ... SELECT ...? > That's what I've been guessing, and why I was asking for a query plan. regards -- Tomas Vondra http://www.2ndQuadrant.com PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services
