On Wed, Apr 24, 2019 at 12:49 PM Andres Freund <and...@anarazel.de> wrote:
> Hi, > > On 2019-04-24 12:46:15 +0800, Paul Guo wrote: > > This is, in theory, not a 100% bug, but it is probably not unusual to see > > conflicts of files between postgresql sqls and other applications on the > > same node so I think the fix is needed. I checked all code that calls > > AllocateFile() and wrote a simple patch to do sanity check (if the file > > exists it must be a regular file) for those files which are probably out > of > > the postgres data directories which we probably want to ignore. This is > > actually not a perfect fix since it is not atomic (check and open), but > it > > should fix most of the scenarios. To be perfect, we might want to > refactor > > AllocateFile() to allow atomic check&create using either 'x' in fopen() > > or O_EXCL in open(), also it seems that we might not want to create temp > > file for AllocateFile() with fixed filenames. This is beyond of this > patch > > of course. > > This seems like a bad idea to me. IMO we want to support using a pipe > etc here. If the admin creates a fifo like this without attaching a > program it seems like it's their fault. > Oh, I never know this application scenario before. So yes, for this, we need to keep the current code logic in copy code. > > Greetings, > > Andres Freund >
