Marcus Griep <marcus@xxxxxxxx> wrote:
> Currently, git-svn would create a temp file on four occasions:
> 1. Reading a blob out of the object db
> 2. Creating a delta from svn
> 3. Hashing and writing a blob into the object db
> 4. Reading a blob out of the object db (in another place in code)
>
> Any time git-svn did the above, it would dutifully create and then
> delete said temp file. Unfortunately, this means that between 2-4
> temporary files are created/deleted per file 'add/modify'-ed in
> svn (O(n)). This causes significant overhead and helps the inode
> counter to spin beautifully.
>
> By its nature, git-svn is a serial beast. Thus, reusing a temp file
> does not pose significant problems. "truncate and seek" takes much
> less time than "unlink and create". This patch centralizes the
> tempfile creation and holds onto the tempfile until they are deleted
> on exit. This significantly reduces file overhead, now requiring
> at most three (3) temp files per run (O(1)).
>
> Signed-off-by: Marcus Griep <marcus@xxxxxxxx>
Acked-by: Eric Wong <normalperson@xxxxxxxx>
> ---
> git-svn.perl | 35 ++++++++++++++++++-----------------
> 1 files changed, 18 insertions(+), 17 deletions(-)
>
> diff --git a/git-svn.perl b/git-svn.perl
> index 4dc3380..9eae5e8 100755
> --- a/git-svn.perl
> +++ b/git-svn.perl
> @@ -1265,7 +1265,7 @@ sub md5sum {
> my $arg = shift;
> my $ref = ref $arg;
> my $md5 = Digest::MD5->new();
> - if ($ref eq 'GLOB' || $ref eq 'IO::File') {
> + if ($ref eq 'GLOB' || $ref eq 'IO::File' || $ref eq 'File::Temp') {
> $md5->addfile($arg) or croak $!;
> } elsif ($ref eq 'SCALAR') {
> $md5->add($$arg) or croak $!;
> @@ -1328,6 +1328,7 @@ BEGIN {
> }
> }
>
> +
> my (%LOCKFILES, %INDEX_FILES);
> END {
> unlink keys %LOCKFILES if %LOCKFILES;
> @@ -3230,13 +3231,11 @@ sub change_file_prop {
>
> sub apply_textdelta {
> my ($self, $fb, $exp) = @_;
> - my $fh = IO::File->new_tmpfile;
> - $fh->autoflush(1);
> + my $fh = Git::temp_acquire('svn_delta');
> # $fh gets auto-closed() by SVN::TxDelta::apply(),
> # (but $base does not,) so dup() it for reading in close_file
> open my $dup, '<&', $fh or croak $!;
> - my $base = IO::File->new_tmpfile;
> - $base->autoflush(1);
> + my $base = Git::temp_acquire('git_blob');
> if ($fb->{blob}) {
> print $base 'link ' if ($fb->{mode_a} == 120000);
> my $size = $::_repository->cat_blob($fb->{blob}, $base);
> @@ -3251,9 +3250,9 @@ sub apply_textdelta {
> }
> }
> seek $base, 0, 0 or croak $!;
> - $fb->{fh} = $dup;
> + $fb->{fh} = $fh;
> $fb->{base} = $base;
> - [ SVN::TxDelta::apply($base, $fh, undef, $fb->{path}, $fb->{pool}) ];
> + [ SVN::TxDelta::apply($base, $dup, undef, $fb->{path}, $fb->{pool}) ];
> }
>
> sub close_file {
> @@ -3282,22 +3281,25 @@ sub close_file {
> }
> }
>
> - my ($tmp_fh, $tmp_filename) = File::Temp::tempfile(UNLINK => 1);
> + my $tmp_fh = Git::temp_acquire('svn_hash');
> my $result;
> while ($result = sysread($fh, my $string, 1024)) {
> my $wrote = syswrite($tmp_fh, $string, $result);
> defined($wrote) && $wrote == $result
> - or croak("write $tmp_filename: $!\n");
> + or croak("write ",
> + $tmp_fh->filename, ": $!\n");
> }
> defined $result or croak $!;
> - close $tmp_fh or croak $!;
>
> - close $fh or croak $!;
>
> - $hash = $::_repository->hash_and_insert_object($tmp_filename);
> - unlink($tmp_filename);
> + Git::temp_release($fh, 1);
> +
> + $hash = $::_repository->hash_and_insert_object(
> + $tmp_fh->filename);
> $hash =~ /^[a-f\d]{40}$/ or die "not a sha1: $hash\n";
> - close $fb->{base} or croak $!;
> +
> + Git::temp_release($fb->{base}, 1);
> + Git::temp_release($tmp_fh, 1);
> } else {
> $hash = $fb->{blob} or die "no blob information\n";
> }
> @@ -3667,7 +3669,7 @@ sub chg_file {
> } elsif ($m->{mode_b} !~ /755$/ && $m->{mode_a} =~ /755$/) {
> $self->change_file_prop($fbat,'svn:executable',undef);
> }
> - my $fh = IO::File->new_tmpfile or croak $!;
> + my $fh = Git::temp_acquire('git_blob');
> if ($m->{mode_b} =~ /^120/) {
> print $fh 'link ' or croak $!;
> $self->change_file_prop($fbat,'svn:special','*');
> @@ -3686,9 +3688,8 @@ sub chg_file {
> my $atd = $self->apply_textdelta($fbat, undef, $pool);
> my $got = SVN::TxDelta::send_stream($fh, @$atd, $pool);
> die "Checksum mismatch\nexpected: $exp\ngot: $got\n" if ($got ne $exp);
> + Git::temp_release($fh, 1);
> $pool->clear;
> -
> - close $fh or croak $!;
> }
>
> sub D {
> --
> 1.6.0.rc2.6.g8eda3
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