On Tue, Aug 17, 2021 at 10:54 AM Amit Kapila <amit.kapil...@gmail.com> wrote: > > On Mon, Aug 16, 2021 at 8:18 PM Dilip Kumar <dilipbal...@gmail.com> wrote: > > > > On Fri, Aug 13, 2021 at 9:29 PM Andres Freund <and...@anarazel.de> wrote: > > > > > > I think we can extend this API but I guess it is better to then do it > > > > for dsm-based as well so that these get tracked via resowner. > > > > > > DSM segments are resowner managed already, so it's not obvious that > > > that'd buy > > > us much? Although I guess there could be a few edge cases that'd look > > > cleaner, > > > because we could reliably trigger cleanup in the leader instead of > > > relying on > > > dsm detach hooks + refcounts to manage when a set is physically deleted? > > > > > > > In an off-list discussion with Thomas and Amit, we tried to discuss > > how to clean up the shared files set in the current use case. Thomas > > suggested that instead of using individual shared fileset for storing > > the data for each XID why don't we just create a single shared fileset > > for complete worker lifetime and when the worker is exiting we can > > just remove that shared fileset. And for storing XID data, we can > > just create the files under the same shared fileset and delete those > > files when we longer need them. I like this idea and it looks much > > cleaner, after this, we can get rid of the special cleanup mechanism > > using 'filesetlist'. I have attached a patch for the same. > > > > It seems to me that this idea would obviate any need for resource > owners as we will have only one fileset now. I have a few initial > comments on the patch: >
One more comment: @@ -2976,39 +2952,17 @@ subxact_info_write(Oid subid, TransactionId xid) .. + /* Try to open the subxact file, if it doesn't exist then create it */ + fd = BufFileOpenShared(xidfileset, path, O_RDWR, true); + if (fd == NULL) + fd = BufFileCreateShared(xidfileset, path); .. Instead of trying to create the file here based on whether it exists or not, can't we create it in subxact_info_add where we are first time allocating memory for subxacts? If that works then in the above code, the file should always exist. -- With Regards, Amit Kapila.
