From: Joey Hess <joeyh@joeyh.name>
Date: Wed, 16 Dec 2015 17:24:45 +0000 (-0400)
Subject: comment
X-Git-Tag: archive/raspbian/10.20250416-2+rpi1~1^2~320^2~184^2~31
X-Git-Url: https://dgit.raspbian.org/?a=commitdiff_plain;h=1a051f4300f9ae56e93527485b1aa7cc0fd12332;p=git-annex.git

comment
---

diff --git a/Database/Keys.hs b/Database/Keys.hs
index 62c7c25eb4..d4b5b33574 100644
--- a/Database/Keys.hs
+++ b/Database/Keys.hs
@@ -54,7 +54,14 @@ Content
   KeyCacheIndex key cache
 |]
 
-{- Opens the database, creating it if it doesn't exist yet. -}
+{- Opens the database, creating it if it doesn't exist yet.
+ -
+ - Multiple readers and writers can have the database open at the same
+ - time. Database.Handle deals with the concurrency issues.
+ - The lock is held while opening the database, so that when
+ - the database doesn't exist yet, one caller wins the lock and
+ - can create it undisturbed.
+ -}
 openDb :: Annex DbHandle
 openDb = withExclusiveLock gitAnnexKeysDbLock $ do
 	dbdir <- fromRepo gitAnnexKeysDb