[PATCH] cogito: Avoid slowness when timewarping large trees.
From: Jeff King <hidden>
Date: 2016-06-15 22:42:22
Subsystem:
the rest · Maintainer:
Linus Torvalds
tree_timewarp was calling read, egrep, and rm in an O(N) loop where N is the number of changed files between two trees. This caused a bottleneck when seeking/switching/merging between trees with many changed files. On the historical linux tree, the time to cg-seek from the head to the initial commit (a change of 19099 files) dropped from 2m35s to 21s. --- cg-Xlib | 9 +++------ 1 files changed, 3 insertions(+), 6 deletions(-) a9a160c0bd63973c53ba3aa74650728135d23ac7
diff --git a/cg-Xlib b/cg-Xlib
index a2f28cf..ceddeeb 100644
--- a/cg-Xlib
+++ b/cg-Xlib@@ -345,12 +345,9 @@ tree_timewarp() # Kill gone files git-diff-tree -r "$base" "$branch" | - while IFS=$'\t' read header file; do - # match ":100755 000000 14d43b1abf... 000000000... D" - if echo "$header" | egrep "^:([^ ][^ ]* ){4}D" >/dev/null; then - rm -- "$file" - fi - done + # match ":100755 000000 14d43b1abf... 000000000... D" + sed -ne 's/^:\([^ ][^ ]* \)\{4\}D\t//p' | + xargs rm -- git-checkout-index -u -f -a # FIXME: Can produce bogus "contains only garbage" messages.
--
1.2.4