On 166, 06 15, 2005 at 04:54:21PM +1000, Curtis Maloney
wrote:>
> Greetings,
>
> I noticed a while back someone posted a patch/plugin that allowed
> Dovecot to use compressed mbox files. I'm now wondering how far that
would
> put us from having compressed maildir?
Been here, done that :) You can try the attached patch, it's a little ugly,
but
works on the production server for more than 2 months.
> I have a server with more CPU than
> disk space, and while I can buy more HDD space, my backup solution
doesn't
> make that practical.
>
> It seems to me that when looking for a message file, if it ends in
> .gz unpack it, and otherwise everything acts as normal. Worst case, this
> is one strcat() and a stat() slower to find.
>
> Newly delivered messages could remain unpacked, and a cron job could come
> by whenever to compress old/large/un-looked-at-for-months messages. So,
> new and frequently referenced messages would be as fast as ever, and older
> messages would be slower.
>
> I would love to dive in an do this myself, but 1- my time is very
> very limited, working two jobs, and 2- I'm not running 1.0 yet, as it
> apparently still doesn't support my Thunderbird users tagging their
> messages (am I wrong? please tell me I'm wrong... I want to upgrade!
:)
--
Andrey Panin | Linux and UNIX system administrator
pazke at donpac.ru | PGP key: wwwkeys.pgp.net
-------------- next part --------------
diff -urdpNX /usr/share/dontdiff -x debian
dovecot-1.0-test73.vanilla/configure.in dovecot-1.0-test73/configure.in
--- dovecot-1.0-test73.vanilla/configure.in 2005-06-15 01:43:30.000000000 +0400
+++ dovecot-1.0-test73/configure.in 2005-06-15 11:57:29.000000000 +0400
@@ -266,6 +266,8 @@ dnl **
dnl ** just some generic stuff...
dnl **
+LIBS="-lz"
+
AC_CHECK_FUNC(socket, [], [
AC_CHECK_LIB(socket, socket, [
LIBS="$LIBS -lsocket"
diff -urdpNX /usr/share/dontdiff -x debian
dovecot-1.0-test73.vanilla/src/lib/istream-zlib.c
dovecot-1.0-test73/src/lib/istream-zlib.c
--- dovecot-1.0-test73.vanilla/src/lib/istream-zlib.c 1970-01-01
03:00:00.000000000 +0300
+++ dovecot-1.0-test73/src/lib/istream-zlib.c 2005-06-15 11:54:54.000000000
+0400
@@ -0,0 +1,190 @@
+/* Copyright (C) 2005 Timo Sirainen */
+
+#include "lib.h"
+#include "istream-internal.h"
+#include "istream-zlib.h"
+
+#include <zlib.h>
+
+#define I_STREAM_MIN_SIZE 4096
+
+struct zlib_istream {
+ struct _istream istream;
+
+ size_t max_buffer_size;
+
+ int fd;
+ gzFile *file;
+ buffer_t *buffer;
+ uoff_t cached_size;
+};
+
+static void _close(struct _iostream *stream)
+{
+ struct zlib_istream *zstream = (struct zlib_istream *)stream;
+
+ if (zstream->file != NULL) {
+ gzclose(zstream->file);
+ zstream->file = NULL;
+ }
+}
+
+static void _destroy(struct _iostream *stream __attr_unused__)
+{
+}
+
+static void _set_max_buffer_size(struct _iostream *stream, size_t max_size)
+{
+ struct zlib_istream *zstream = (struct zlib_istream *)stream;
+
+ zstream->max_buffer_size = max_size;
+}
+
+static void i_stream_grow_buffer(struct _istream *stream, size_t bytes)
+{
+ struct zlib_istream *zstream = (struct zlib_istream *)stream;
+ size_t old_size;
+
+ old_size = stream->buffer_size;
+
+ stream->buffer_size = stream->pos + bytes;
+ if (stream->buffer_size <= I_STREAM_MIN_SIZE)
+ stream->buffer_size = I_STREAM_MIN_SIZE;
+ else {
+ stream->buffer_size + pool_get_exp_grown_size(stream->iostream.pool,
+ old_size, stream->buffer_size);
+ }
+
+ if (zstream->max_buffer_size > 0 &&
+ stream->buffer_size > zstream->max_buffer_size)
+ stream->buffer_size = zstream->max_buffer_size;
+
+ stream->buffer = stream->w_buffer + p_realloc(stream->iostream.pool,
stream->w_buffer,
+ old_size, stream->buffer_size);
+}
+
+static void i_stream_compress(struct _istream *stream)
+{
+ memmove(stream->w_buffer, stream->w_buffer + stream->skip,
+ stream->pos - stream->skip);
+ stream->pos -= stream->skip;
+
+ stream->skip = 0;
+}
+
+static ssize_t _read(struct _istream *stream)
+{
+ struct zlib_istream *zstream = (struct zlib_istream *)stream;
+ size_t size;
+ int ret;
+
+ if (stream->istream.closed)
+ return -1;
+
+ stream->istream.stream_errno = 0;
+
+ if (stream->pos == stream->buffer_size) {
+ if (stream->skip > 0) {
+ /* remove the unused bytes from beginning of buffer */
+ i_stream_compress(stream);
+ } else if (zstream->max_buffer_size == 0 ||
+ stream->buffer_size < zstream->max_buffer_size) {
+ /* buffer is full - grow it */
+ i_stream_grow_buffer(stream, I_STREAM_MIN_SIZE);
+ }
+
+ if (stream->pos == stream->buffer_size)
+ return -2; /* buffer full */
+ }
+
+ size = stream->buffer_size - stream->pos;
+
+ ret = -1;
+
+ ret = gzread(zstream->file, stream->w_buffer + stream->pos, size);
+ if (ret == 0) {
+ /* EOF */
+ stream->istream.eof = TRUE;
+ return -1;
+ }
+
+ if (ret < 0) {
+ if (errno == EINTR || errno == EAGAIN)
+ ret = 0;
+ else {
+ stream->istream.eof = TRUE;
+ stream->istream.stream_errno = errno;
+ return -1;
+ }
+ }
+
+ stream->pos += ret;
+ i_assert(ret != 0);
+ return ret;
+}
+
+static void _seek(struct _istream *stream, uoff_t v_offset)
+{
+ struct zlib_istream *zstream = (struct zlib_istream *) stream;
+
+ gzseek(zstream->file, v_offset, SEEK_SET);
+
+ stream->istream.stream_errno = 0;
+ stream->istream.v_offset = v_offset;
+ stream->skip = stream->pos = 0;
+}
+
+static const struct stat *_stat(struct _istream *stream)
+{
+ struct zlib_istream *zstream = (struct zlib_istream *) stream;
+ size_t size;
+
+ if (fstat(zstream->fd, &stream->statbuf) < 0) {
+ i_error("zlib_istream.fstat() failed: %m");
+ return NULL;
+ }
+
+ if (zstream->cached_size == (uoff_t)-1) {
+ uoff_t old_offset = stream->istream.v_offset;
+ do {
+ (void)i_stream_get_data(&stream->istream, &size);
+ i_stream_skip(&stream->istream, size);
+ } while (_read(stream) > 0);
+
+ zstream->cached_size = stream->istream.v_offset;
+ i_stream_seek(&stream->istream, old_offset);
+ }
+ stream->statbuf.st_size = zstream->cached_size;
+ return &stream->statbuf;
+}
+
+static void _sync(struct _istream *stream)
+{
+ struct zlib_istream *zstream = (struct zlib_istream *) stream;
+
+ zstream->cached_size = (uoff_t)-1;
+}
+
+struct istream *i_stream_create_zlib(int fd, pool_t pool)
+{
+ struct zlib_istream *zstream;
+
+ zstream = p_new(pool, struct zlib_istream, 1);
+ zstream->fd = fd;
+ zstream->file = gzdopen(fd, "r");
+ zstream->cached_size = (uoff_t)-1;
+
+ zstream->istream.iostream.close = _close;
+ zstream->istream.iostream.destroy = _destroy;
+ zstream->istream.iostream.set_max_buffer_size = _set_max_buffer_size;
+
+ zstream->istream.read = _read;
+ zstream->istream.seek = _seek;
+ zstream->istream.stat = _stat;
+ zstream->istream.sync = _sync;
+
+ zstream->istream.istream.seekable = TRUE;
+ return _i_stream_create(&zstream->istream, pool, fd, 0);
+}
diff -urdpNX /usr/share/dontdiff -x debian
dovecot-1.0-test73.vanilla/src/lib/istream-zlib.h
dovecot-1.0-test73/src/lib/istream-zlib.h
--- dovecot-1.0-test73.vanilla/src/lib/istream-zlib.h 1970-01-01
03:00:00.000000000 +0300
+++ dovecot-1.0-test73/src/lib/istream-zlib.h 2005-06-15 11:54:54.000000000
+0400
@@ -0,0 +1,6 @@
+#ifndef __ISTREAM_ZLIB_H
+#define __ISTREAM_ZLIB_H
+
+struct istream *i_stream_create_zlib(int fd, pool_t pool);
+
+#endif
diff -urdpNX /usr/share/dontdiff -x debian
dovecot-1.0-test73.vanilla/src/lib/Makefile.am
dovecot-1.0-test73/src/lib/Makefile.am
--- dovecot-1.0-test73.vanilla/src/lib/Makefile.am 2005-03-29 19:44:42.000000000
+0400
+++ dovecot-1.0-test73/src/lib/Makefile.am 2005-06-15 11:54:54.000000000 +0400
@@ -26,6 +26,7 @@ liblib_a_SOURCES = \
istream-limit.c \
istream-mmap.c \
istream-seekable.c \
+ istream-zlib.c \
ioloop.c \
ioloop-notify-none.c \
ioloop-notify-dn.c \
@@ -96,6 +97,7 @@ noinst_HEADERS = \
istream.h \
istream-internal.h \
istream-seekable.h \
+ istream-zlib.h \
ioloop.h \
ioloop-internal.h \
lib.h \
diff -urdpNX /usr/share/dontdiff -x debian
dovecot-1.0-test73.vanilla/src/lib-storage/index/maildir/maildir-mail.c
dovecot-1.0-test73/src/lib-storage/index/maildir/maildir-mail.c
--- dovecot-1.0-test73.vanilla/src/lib-storage/index/maildir/maildir-mail.c
2005-06-09 18:40:31.000000000 +0400
+++ dovecot-1.0-test73/src/lib-storage/index/maildir/maildir-mail.c 2005-06-15
12:02:13.000000000 +0400
@@ -5,6 +5,7 @@
#include "index-mail.h"
#include "maildir-storage.h"
#include "maildir-uidlist.h"
+#include "istream-zlib.h"
#include <fcntl.h>
#include <unistd.h>
@@ -57,6 +58,17 @@ maildir_open_mail(struct maildir_mailbox
return NULL;
}
+ {
+ static const unsigned char zlib_magic[3] = { 0x1F, 0x8B, 8 };
+ unsigned char magic[3] = { };
+
+ read(fd, magic, sizeof(magic));
+ lseek(fd, 0, SEEK_SET);
+
+ if (memcmp(magic, zlib_magic, sizeof(magic)) == 0)
+ return i_stream_create_zlib(fd, default_pool);
+ }
+
if (mbox->ibox.mail_read_mmaped) {
return i_stream_create_mmap(fd, default_pool,
MAIL_MMAP_BLOCK_SIZE, 0, 0, TRUE);
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 189 bytes
Desc: Digital signature
URL:
<http://dovecot.org/pipermail/dovecot/attachments/20050615/857422ad/attachment-0001.bin>