doc: add some recommendations around slow HDDs

[public-inbox.git] / examples / grok-pull.post_update_hook.sh

diff --git a/examples/grok-pull.post_update_hook.sh b/examples/grok-pull.post_update_hook.sh
index 3ead394408eb68f80950f78b6326f2ee5e1f471c..ec4ae93e829dc93eee66b3dbfc4a58bd28c49e4b 100755 (executable)
--- a/examples/grok-pull.post_update_hook.sh
+++ b/examples/grok-pull.post_update_hook.sh
@@ -1,4 +1,9 @@
 #!/bin/sh
+
+# use flock(1) from util-linux to avoid seek contention on slow HDDs
+# when using multiple `pull_threads' with grok-pull:
+# [ "${FLOCKER}" != "$0" ] && exec env FLOCKER="$0" flock "$0" "$0" "$@" || :
+
 # post_update_hook for repos.conf as used by grok-pull, takes a full
 # git repo path as it's first and only arg.
 full_git_dir="$1"
@@ -119,6 +124,7 @@ then
                : v2 inboxes may be init-ed with an empty msgmap
                ;;
        *)
+               # if on HDD and limited RAM, add `-j0' w/ public-inbox 1.6.0+
                $EATMYDATA public-inbox-index -v "$inbox_dir"
                ;;
        esac