msgmap: disable CoW for tmp_clone, too

The temporary clone starts as large as the full msgmap
and deletes will write to it randomly.  So ensure it
doesn't get fragmented and slower as time goes on.

diff --git a/lib/PublicInbox/Msgmap.pm b/lib/PublicInbox/Msgmap.pm
index 51b6a68c8547e81a4eaf9168000354fea548085a..c85e7796cbd4512f2c286628a4eff8f04aed9388 100644 (file)
--- a/lib/PublicInbox/Msgmap.pm
+++ b/lib/PublicInbox/Msgmap.pm
@@ -14,6 +14,7 @@ use DBI;
 use DBD::SQLite;
 use File::Temp qw(tempfile);
 use PublicInbox::Over;
+use PublicInbox::Spawn;
 
 sub new {
        my ($class, $git_dir, $writable) = @_;
@@ -50,6 +51,7 @@ sub new_file {
 sub tmp_clone {
        my ($self, $dir) = @_;
        my ($fh, $fn) = tempfile('msgmap-XXXXXXXX', EXLOCK => 0, DIR => $dir);
+       PublicInbox::Spawn::set_nodatacow(fileno($fh));
        my $tmp;
        if ($self->{dbh}->can('sqlite_backup_to_dbh')) {
                $tmp = ref($self)->new_file($fn, 2);