[sql] Don't persist data in journal files.
Using journal_mode=PERSIST in combination with secure_delete=ON is
probably not quite right. Switch to journal_mode=TRUNCATE for now,
while considering whether that combination should overwrite (or be
forbidden).
BUG=493008
Review URL: https://codereview.chromium.org/1159033004
Cr-Commit-Position: refs/heads/master@{#332309}
diff --git a/sql/connection.cc b/sql/connection.cc
index b91234b..8720985 100644
--- a/sql/connection.cc
+++ b/sql/connection.cc
@@ -988,12 +988,10 @@
// DELETE (default) - delete -journal file to commit.
// TRUNCATE - truncate -journal file to commit.
// PERSIST - zero out header of -journal file to commit.
- // journal_size_limit provides size to trim to in PERSIST.
- // TODO(shess): Figure out if PERSIST and journal_size_limit really
- // matter. In theory, it keeps pages pre-allocated, so if
- // transactions usually fit, it should be faster.
- ignore_result(Execute("PRAGMA journal_mode = PERSIST"));
- ignore_result(Execute("PRAGMA journal_size_limit = 16384"));
+ // TRUNCATE should be faster than DELETE because it won't need directory
+ // changes for each transaction. PERSIST may break the spirit of using
+ // secure_delete.
+ ignore_result(Execute("PRAGMA journal_mode = TRUNCATE"));
const base::TimeDelta kBusyTimeout =
base::TimeDelta::FromSeconds(kBusyTimeoutSeconds);
