1:59 a.m.
Chris Lalancette wrote:
Jim Meyering wrote:
> While this patch stays minimal by simply adding XZ/xz to the list,
> I think it would be better to remove lzma, since it uses
> an inferior format (which lacks an integrity check), and
> has been effectively subsumed by xz.
>
> Let me know if you'd like that, and I'll prepare the slightly
> more invasive patch.
I'm on the fence about it. While I do understand the situation now (thanks for
explaining), I think keeping lzma for compatibility with older distros might be
a good idea. Either way, we have to keep the LZMA slot in the enum "free",
since it's part of the on-disk ABI for the save format. And on that note...
> diff --git a/src/qemu_driver.c b/src/qemu_driver.c
> index f64d70b..7b64712 100644
> --- a/src/qemu_driver.c
> +++ b/src/qemu_driver.c
> @@ -3622,7 +3622,8 @@ enum qemud_save_formats {
> QEMUD_SAVE_FORMAT_RAW,
> QEMUD_SAVE_FORMAT_GZIP,
> QEMUD_SAVE_FORMAT_BZIP2,
> - QEMUD_SAVE_FORMAT_LZMA,
> + QEMUD_SAVE_FORMAT_LZMA, /* deprecated, in favor of xz */
> + QEMUD_SAVE_FORMAT_XZ,
> QEMUD_SAVE_FORMAT_LZOP,
> };
You'll need to add QEMUD_SAVE_FORMAT_XZ to the end of the enum, to maintain
on-disk compatibility. Otherwise it looks good.
Thanks. Good point. Here's an amended patch:
Note, I've reordered the if/else placement to match enum member
ordering, too.
From 24309516094b058cce9f5eb123877bd5eec2cfc2 Mon Sep 17 00:00:00 2001
From: Jim Meyering <meyering(a)redhat.com>
Date: Tue, 8 Sep 2009 20:52:37 +0200
Subject: [PATCH] also allow use of XZ for Qemu image compression
* src/qemu_driver.c (enum qemud_save_formats) [QEMUD_SAVE_FORMAT_XZ]:
New member.
[QEMUD_SAVE_FORMAT_LZMA]: Mark as deprecated.
(qemudDomainSave, qemudDomainRestore): Handle the new member.
* src/qemu.conf: Mention xz, too.
---
src/qemu.conf | 2 +-
src/qemu_driver.c | 10 +++++++++-
2 files changed, 10 insertions(+), 2 deletions(-)
diff --git a/src/qemu.conf b/src/qemu.conf
index 06babc4..342bb8a 100644
--- a/src/qemu.conf
+++ b/src/qemu.conf
@@ -134,7 +134,7 @@
# memory from the domain is dumped out directly to a file. If you have
# guests with a large amount of memory, however, this can take up quite
# a bit of space. If you would like to compress the images while they
-# are being saved to disk, you can also set "gzip", "bzip2",
"lzma"
+# are being saved to disk, you can also set "gzip", "bzip2",
"lzma", "xz",
# or "lzop" for save_image_format. Note that this means you slow down
# the process of saving a domain in order to save disk space.
#
diff --git a/src/qemu_driver.c b/src/qemu_driver.c
index f64d70b..99b3390 100644
--- a/src/qemu_driver.c
+++ b/src/qemu_driver.c
@@ -3622,8 +3622,9 @@ enum qemud_save_formats {
QEMUD_SAVE_FORMAT_RAW,
QEMUD_SAVE_FORMAT_GZIP,
QEMUD_SAVE_FORMAT_BZIP2,
- QEMUD_SAVE_FORMAT_LZMA,
+ QEMUD_SAVE_FORMAT_LZMA, /* deprecated, in favor of xz */
QEMUD_SAVE_FORMAT_LZOP,
+ QEMUD_SAVE_FORMAT_XZ,
};
struct qemud_save_header {
@@ -3666,6 +3667,8 @@ static int qemudDomainSave(virDomainPtr dom,
header.compressed = QEMUD_SAVE_FORMAT_LZMA;
else if (STREQ(driver->saveImageFormat, "lzop"))
header.compressed = QEMUD_SAVE_FORMAT_LZOP;
+ else if (STREQ(driver->saveImageFormat, "xz"))
+ header.compressed = QEMUD_SAVE_FORMAT_XZ;
else {
qemudReportError(dom->conn, dom, NULL, VIR_ERR_OPERATION_FAILED,
"%s", _("Invalid save image format specified in
configuration file"));
@@ -3761,6 +3764,9 @@ static int qemudDomainSave(virDomainPtr dom,
else if (header.compressed == QEMUD_SAVE_FORMAT_LZOP)
internalret = virAsprintf(&command, "migrate \"exec:"
"lzop -c >> '%s'
2>/dev/null\"", safe_path);
+ else if (header.compressed == QEMUD_SAVE_FORMAT_XZ)
+ internalret = virAsprintf(&command, "migrate \"exec:"
+ "xz -c >> '%s'
2>/dev/null\"", safe_path);
else {
qemudReportError(dom->conn, dom, NULL, VIR_ERR_INTERNAL_ERROR,
_("Invalid compress format %d"),
@@ -4385,6 +4391,8 @@ static int qemudDomainRestore(virConnectPtr conn,
intermediate_argv[0] = "lzma";
else if (header.compressed == QEMUD_SAVE_FORMAT_LZOP)
intermediate_argv[0] = "lzop";
+ else if (header.compressed == QEMUD_SAVE_FORMAT_XZ)
+ intermediate_argv[0] = "xz";
else if (header.compressed != QEMUD_SAVE_FORMAT_RAW) {
qemudReportError(conn, NULL, NULL, VIR_ERR_OPERATION_FAILED,
_("Unknown compressed save format %d"),
--
1.6.5.rc0.164.g5f6b0