From 230bc98f7a2a49eb472d184bdec91fd3096384b3 Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Thu, 17 Feb 2022 11:08:24 -0500 Subject: NFS: Improve heuristic for readdirplus The heuristic for readdirplus is designed to try to detect 'ls -l' and similar patterns. It does so by looking for cache hit/miss patterns in both the attribute cache and in the dcache of the files in a given directory, and then sets a flag for the readdirplus code to interpret. The problem with this approach is that a single attribute or dcache miss can cause the NFS code to force a refresh of the attributes for the entire set of files contained in the directory. To be able to make a more nuanced decision, let's sample the number of hits and misses in the set of open directory descriptors. That allows us to set thresholds at which we start preferring READDIRPLUS over regular READDIR, or at which we start to force a re-read of the remaining readdir cache using READDIRPLUS. Signed-off-by: Trond Myklebust --- fs/nfs/internal.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'fs/nfs/internal.h') diff --git a/fs/nfs/internal.h b/fs/nfs/internal.h index b5398af53c7f..194840a97e3a 100644 --- a/fs/nfs/internal.h +++ b/fs/nfs/internal.h @@ -366,8 +366,8 @@ extern struct nfs_client *nfs_init_client(struct nfs_client *clp, const struct nfs_client_initdata *); /* dir.c */ -extern void nfs_advise_use_readdirplus(struct inode *dir); -extern void nfs_force_use_readdirplus(struct inode *dir); +extern void nfs_readdir_record_entry_cache_hit(struct inode *dir); +extern void nfs_readdir_record_entry_cache_miss(struct inode *dir); extern unsigned long nfs_access_cache_count(struct shrinker *shrink, struct shrink_control *sc); extern unsigned long nfs_access_cache_scan(struct shrinker *shrink, -- cgit v1.2.3-58-ga151