diff options
Diffstat (limited to 'git-deltafy-script')
| -rwxr-xr-x[-rw-r--r--] | git-deltafy-script | 57 |
1 files changed, 42 insertions, 15 deletions
diff --git a/git-deltafy-script b/git-deltafy-script index f63cf07..21a9569 100644..100755 --- a/git-deltafy-script +++ b/git-deltafy-script @@ -1,40 +1,67 @@ #!/bin/bash -# Script to deltafy an entire GIT repository based on the commit list. +# Example script to deltafy an entire GIT repository based on the commit list. # The most recent version of a file is the reference and previous versions # are made delta against the best earlier version available. And so on for -# successive versions going back in time. This way the delta overhead is -# pushed towards older version of any given file. -# -# NOTE: the "best earlier version" is not implemented in mkdelta yet -# and therefore only the next eariler version is used at this time. -# -# TODO: deltafy tree objects as well. +# successive versions going back in time. This way the increasing delta +# overhead is pushed towards older versions of any given file. # # The -d argument allows to provide a limit on the delta chain depth. -# If 0 is passed then everything is undeltafied. +# If 0 is passed then everything is undeltafied. Limiting the delta +# depth is meaningful for subsequent access performance to old revisions. +# A value of 16 might be a good compromize between performance and good +# space saving. Current default is unbounded. +# +# The --max-behind=30 argument is passed to git-mkdelta so to keep +# combinations and memory usage bounded a bit. If you have lots of memory +# and CPU power you may remove it (or set to 0) to let git-mkdelta find the +# best delta match regardless of the number of revisions for a given file. +# You can also make the value smaller to make it faster and less +# memory hungry. A value of 5 ought to still give pretty good results. +# When set to 0 or ommitted then look behind is unbounded. Note that +# git-mkdelta might die with a segmentation fault in that case if it +# runs out of memory. Note that the GIT repository will still be consistent +# even if git-mkdelta dies unexpectedly. set -e depth= [ "$1" == "-d" ] && depth="--max-depth=$2" && shift 2 +function process_list() { + if [ "$list" ]; then + echo "Processing $curr_file" + echo "$head $list" | xargs git-mkdelta $depth --max-behind=30 -v + fi +} + curr_file="" git-rev-list HEAD | -git-diff-tree -r --stdin | -awk '/^:/ { if ($5 == "M" || $5 == "N") print $4, $6 }' | +git-diff-tree -r -t --stdin | +awk '/^:/ { if ($5 == "M" || $5 == "N") print $4, $6; + if ($5 == "M") print $3, $6 }' | LC_ALL=C sort -s -k 2 | uniq | while read sha1 file; do if [ "$file" == "$curr_file" ]; then list="$list $sha1" else - if [ "$list" ]; then - echo "Processing $curr_file" - echo "$head $list" | xargs git-mkdelta $depth -v - fi + process_list curr_file="$file" list="" head="$sha1" fi done +process_list + +curr_file="root directory" +head="" +list="$( + git-rev-list HEAD | + while read commit; do + git-cat-file commit $commit | + sed -n 's/tree //p;Q' + done + )" +process_list + |