Thomas Munro <thomas.munro@xxxxxxxxxxxxxxxx> writes: > So you have 16GB of RAM and here we're failing to posix_fallocate() > 50MB (actually we can't tell if it's the ftruncate() or > posix_fallocate() call that failed, but the latter seems more likely > since the former just creates a big hole in the underlying tmpfs > file). Can you share the query plan (EXPLAIN SELECT ...)? I wonder if OP is running with a tmpfs size setting that's less than the traditional Linux default of half of physical RAM size. regards, tom lane
