diff options
Diffstat (limited to 'nix/libstore')
| -rw-r--r-- | nix/libstore/gc.cc | 4 | ||||
| -rw-r--r-- | nix/libstore/local-store.hh | 3 | ||||
| -rw-r--r-- | nix/libstore/optimise-store.cc | 15 |
3 files changed, 15 insertions, 7 deletions
diff --git a/nix/libstore/gc.cc b/nix/libstore/gc.cc index e1d0765154..16519116e4 100644 --- a/nix/libstore/gc.cc +++ b/nix/libstore/gc.cc @@ -606,7 +606,9 @@ void LocalStore::removeUnusedLinks(const GCState & state) throw SysError(format("statting `%1%'") % path); #endif - if (st.st_nlink != 1) { + /* Drop links for files smaller than 'deduplicationMinSize', even if + they have more than one hard link. */ + if (st.st_nlink != 1 && st.st_size >= deduplicationMinSize) { actualSize += st.st_size; unsharedSize += (st.st_nlink - 1) * st.st_size; continue; diff --git a/nix/libstore/local-store.hh b/nix/libstore/local-store.hh index 9ba37219da..20d3c3c893 100644 --- a/nix/libstore/local-store.hh +++ b/nix/libstore/local-store.hh @@ -292,4 +292,7 @@ void canonicaliseTimestampAndPermissions(const Path & path); MakeError(PathInUse, Error); +/* Size below which a file is not considered for deduplication. */ +extern const size_t deduplicationMinSize; + } diff --git a/nix/libstore/optimise-store.cc b/nix/libstore/optimise-store.cc index eb303ab4c3..9fd6f3cb35 100644 --- a/nix/libstore/optimise-store.cc +++ b/nix/libstore/optimise-store.cc @@ -15,6 +15,9 @@ namespace nix { +/* Any file smaller than this is not considered for deduplication. + Keep in sync with (guix store deduplication). */ +const size_t deduplicationMinSize = 8192; static void makeWritable(const Path & path) { @@ -105,12 +108,12 @@ void LocalStore::optimisePath_(OptimiseStats & stats, const Path & path, InodeHa return; } - /* We can hard link regular files and maybe symlinks. */ - if (!S_ISREG(st.st_mode) -#if CAN_LINK_SYMLINK - && !S_ISLNK(st.st_mode) -#endif - ) return; + /* We can hard link regular files (and maybe symlinks), but do that only + for files larger than some threshold. This avoids adding too many + entries to '.links', which would slow down 'removeUnusedLinks' while + saving little space. */ + if (!S_ISREG(st.st_mode) || ((size_t) st.st_size) < deduplicationMinSize) + return; /* Sometimes SNAFUs can cause files in the store to be modified, in particular when running programs as root under |