Yes, a DOCUMENTED and configurable limit may be useful... If there is some way to monitor it, that would help too. Because "hidden" limits are a pain... If I'm about to hit a brick wall, I'd like to at least see it coming... Regards, Brian Cowan ClearCase/VersionVault SWAT Mob: +1 (978) 907-2334 hcltechsw.com On Tue, Jul 23, 2024 at 1:22 PM Frank Filz <ffilzlnx@xxxxxxxxxxxxxx> wrote: > > Any server is likely to have some limit based on the memory use for the open state. > > We recently introduced a configuration to limit the number of opens per clientid in nfs-ganesha for comparison, prior to that it was not specifically limited (and the configuration defaults to no limit) other than we would eventually run out of memory. > > It's probably good to have a limit, but your case suggests a value in that limit being configurable. > > Frank > > > -----Original Message----- > > From: Brian Cowan [mailto:brian.cowan@xxxxxxxxxxxxxxxx] > > Sent: Tuesday, July 23, 2024 7:16 AM > > To: linux-nfs@xxxxxxxxxxxxxxx > > Subject: Limits to number of files opened by remote hosts over NFSv4? > > > > I am responsible for supporting an application that opens LOTS of files over NFS > > from a given host, and potentially a few files/host from a LOT of clients. We've > > run into some "interesting" limitations from other OS's when it comes to > > NFSv4... > > > > Solaris, for example, "only" allows 10K or so files per NFS export to be opened > > over NFSv4. When you have 2500+ client hosts opening files over NFSv4, the > > Solaris NFS server stops responding to "open" requests until an entry in its state > > table is freed up by a file close. Which causes single threaded client processes > > trying to open said files to hang... Luckily we convinced that customer to move > > the clients back to using NFSv3 since they didn't need the additional features of > > V4. > > > > We're also seeing a potential issue with NetApp filers where opening too many > > files from a single host seems to have issues. We're being told that DataOnTAP > > has a per-client-host limit on the number of files in the Openstate pool (and not > > being told what that limit is...) I say "potential" since the only report is from > > things falling apart after moving from AIX 7.2 to 7.3 (meaning there is a non- > > zero chance that this is actually an AIX NFS issue). In this case, NFSv3 is not an > > option since NFSv4 ACLs are required... > > > > Anyway, as a result, I'm trying to find out if the Linux NFSv4 server has a limit on > > either total number of files, total number of files per export, or total files per > > host. >
