I lean toward eventually increasing the default to something more similar to Windows (or at least 5 minutes) to improve some common scenarios, but it looks like Windows sets it to 10 minutes based on this link, but first want to make sure we are grabbing leases in all of the obvious places (and not unnecessarily breaking leases - there are a few places where we aren't sending the lease key and we also are missing setting the parent lease key) See "DirectoryCacheEntriesMax" iand "DormantDirectoryTimeout" in LanmanWorkstation config. The description https://learn.microsoft.com/en-us/windows-server/administration/performance-tuning/role/file-server/is of some of the related parms was a little vague but presumably DirectoryCacheEntriesMax is the number of directories (16) that are cached by default (ie number of directory leases that are held) and DormantDirectoryTimeout (default 600 seconds) is how long they are held. On Fri, Sep 1, 2023 at 4:04 AM Ralph Boehme <slow@xxxxxxxxx> wrote: > > Just wondering: how does a Windows client handle this? Does it use a > timeout too? Which one? 60 seconds still seem rather short. > > -slow > > On 8/31/23 05:52, Steve French wrote: > > updated patch with Barath's suggestion of renaming it from > > /sys/module/cifs/parameters/max_dir_cache to > > /sys/module/cifs/parameters/dir_cache_timeout and also changed it so > > if set to zero we disable > > directory entry caching. > > > > See attached. > > > > On Sun, Aug 27, 2023 at 12:12 AM Steve French <smfrench@xxxxxxxxx> wrote: > >> > >> Currently with directory leases we cache directory contents for a fixed period > >> of time (default 30 seconds) but for many workloads this is too short. Allow > >> configuring the maximum amount of time directory entries are cached when a > >> directory lease is held on that directory (and set default timeout to > >> 60 seconds). > >> Add module load parm "max_dir_cache" > >> > >> For example to set the timeout to 10 minutes you would do: > >> > >> echo 600 > /sys/module/cifs/parameters/max_dir_cache > >> > >> Signed-off-by: Steve French <stfrench@xxxxxxxxxxxxx> > >> --- > >> fs/smb/client/cached_dir.c | 2 +- > >> fs/smb/client/cifsfs.c | 12 ++++++++++++ > >> fs/smb/client/cifsglob.h | 1 + > >> 3 files changed, 14 insertions(+), 1 deletion(-) > >> > >> diff --git a/fs/smb/client/cached_dir.c b/fs/smb/client/cached_dir.c > >> index 2d5e9a9d5b8b..e48a902efd52 100644 > >> --- a/fs/smb/client/cached_dir.c > >> +++ b/fs/smb/client/cached_dir.c > >> @@ -582,7 +582,7 @@ cifs_cfids_laundromat_thread(void *p) > >> return 0; > >> spin_lock(&cfids->cfid_list_lock); > >> list_for_each_entry_safe(cfid, q, &cfids->entries, entry) { > >> - if (time_after(jiffies, cfid->time + HZ * 30)) { > >> + if (time_after(jiffies, cfid->time + HZ * max_dir_cache)) { > >> list_del(&cfid->entry); > >> list_add(&cfid->entry, &entry); > >> cfids->num_entries--; > >> diff --git a/fs/smb/client/cifsfs.c b/fs/smb/client/cifsfs.c > >> index d49fd2bf71b0..7a89718d2a59 100644 > >> --- a/fs/smb/client/cifsfs.c > >> +++ b/fs/smb/client/cifsfs.c > >> @@ -117,6 +117,10 @@ module_param(cifs_max_pending, uint, 0444); > >> MODULE_PARM_DESC(cifs_max_pending, "Simultaneous requests to server for " > >> "CIFS/SMB1 dialect (N/A for SMB3) " > >> "Default: 32767 Range: 2 to 32767."); > >> +unsigned int max_dir_cache = 60; > >> +module_param(max_dir_cache, uint, 0644); > >> +MODULE_PARM_DESC(max_dir_cache, "Number of seconds to cache directory > >> contents for which we have a lease. Default: 60 " > >> + "Range: 1 to 65000 seconds"); > >> #ifdef CONFIG_CIFS_STATS2 > >> unsigned int slow_rsp_threshold = 1; > >> module_param(slow_rsp_threshold, uint, 0644); > >> @@ -1679,6 +1683,14 @@ init_cifs(void) > >> CIFS_MAX_REQ); > >> } > >> > >> + if (max_dir_cache < 1) { > >> + max_dir_cache = 1; > >> + cifs_dbg(VFS, "max_dir_cache timeout set to min of 1 second\n"); > >> + } else if (max_dir_cache > 65000) { > >> + max_dir_cache = 65000; > >> + cifs_dbg(VFS, "max_dir_cache timeout set to max of 65000 seconds\n"); > >> + } > >> + > >> cifsiod_wq = alloc_workqueue("cifsiod", WQ_FREEZABLE|WQ_MEM_RECLAIM, 0); > >> if (!cifsiod_wq) { > >> rc = -ENOMEM; > >> diff --git a/fs/smb/client/cifsglob.h b/fs/smb/client/cifsglob.h > >> index 259e231f8b4f..7aeeaa260cce 100644 > >> --- a/fs/smb/client/cifsglob.h > >> +++ b/fs/smb/client/cifsglob.h > >> @@ -2016,6 +2016,7 @@ extern unsigned int CIFSMaxBufSize; /* max size > >> not including hdr */ > >> extern unsigned int cifs_min_rcv; /* min size of big ntwrk buf pool */ > >> extern unsigned int cifs_min_small; /* min size of small buf pool */ > >> extern unsigned int cifs_max_pending; /* MAX requests at once to server*/ > >> +extern unsigned int max_dir_cache; /* max time for directory lease > >> caching of dir */ > >> extern bool disable_legacy_dialects; /* forbid vers=1.0 and vers=2.0 mounts */ > >> extern atomic_t mid_count; > >> > >> > >> -- > >> Thanks, > >> > >> Steve > > > > > > > -- Thanks, Steve
