On Fri, Jun 22, 2012 at 6:59 AM, Juan Quintela
<address@hidden> wrote:
Hi
As discussed on this week kvm call, here are the migration tree with
XBRLE + huge memory fixes integrated. There were a bug on huge memory
(corrected on the v3 version just sent) and another on XZBRLE patches.
Orit is going to resend patches addressing comments, but here the fix is
integrated already.
How to test?
Compile qemu with trace support:
./configure --enable-trace-backend=simple
Create an event file:
$ cat /tmp/events
savevm_section_start
savevm_section_end
$
Now launch qemu with normal command line:
qemu ..... --trace events=/tmp/events
And when execution finish, you can use a script like the following to
see the stalls that happen:
$ cat ~/counter_simpletrace
$1 ~ /savevm_section_end/ {
/* Print savevm_section_stop line when >100 ms duration */
if ($2 > 50000) {
printf("%s times_missing=%u\n", $0, times_missing++);
}
}
$
And now you can analize:
./scripts/simpletrace.py ./trace-events trace-32554 | awk -f ~/counter_simpletrace
(adjust paths as required)
Notice that this are stalls on the iothread. vcpus stalls can still be
bigger. The number that is tested here is 50ms, so I get cases that are
a bit bigger (between 60-100ms with one 8GB guest that is dirtying 512MB
in a loop.
If you get stalls, or drop connections, please let me know the load.
Thanks, Juan.
The following changes since commit 47ecbdf07ed2c37bdfd2d77137d01bb319ce13da:
libcacard: build fixes (2012-06-21 20:04:24 +0000)
are available in the git repository at:
http://repo.or.cz/r/qemu/quintela.git migration-next
for you to fetch changes up to 0844b46b5d7d8d6fa01134d170b3c48b7f32eab7:
Add XBZRLE statistics (2012-06-22 15:24:15 +0200)
Currently this XBZRLE related stats are only available during the active migration but not
after the completion. Can we get this information even after the completion of the XBZRLE migration (via info migrate) ? It would help to keep track of the final list of cache misses/hits etc.
To the generic migration statistics that gets displayed via "info migrate" can you pl. consider adding the duration of Stage3 (i.e. "Downtime") as measured on the source host (yes there is probably some time spent in the resuming of the guest on the destination host...).
Ideally this "Downtime" should be the pretty close to the pre-defined downtime (i.e. default value(30ms?) or whatever the user set it to via migrate_set_downtime command). But it looks like on larger guests that is not the case...
Still reviewing the code and testing it out...
Thanks
Vinod
----------------------------------------------------------------
Isaku Yamahata (1):
Add MigrationParams structure
Juan Quintela (8):
Add spent time for migration
Add tracepoints for savevm section start/end
No need to iterate if we already are over the limit
Only TCG needs TLB handling
Only calculate expected_time for stage 2
Exit loop if we have been there too long
dirty bitmap: abstract its use
Maintain the number of dirty pages
Orit Wasserman (13):
Add missing check for host_from_stream_offset return value for RAM_SAVE_FLAG_PAGE
Add migration capabilites
Add XBZRLE documentation
Add cache handling functions
Add uleb encoding/decoding functions
Add save_block_hdr function
Add debugging infrastructure
Change ram_save_block to return -1 if there are no more changes
Add migration_end function
Add xbzrle_encode_buffer and xbzrle_decode_buffer functions
Add XBZRLE to ram_save_block and ram_save_live
Add set_cachesize command
Add XBZRLE statistics
Makefile.objs | 1 +
arch_init.c | 378 ++++++++++++++++++++++++++++++++++++++++++++------
block-migration.c | 8 +-
cache.c | 219 +++++++++++++++++++++++++++++
cpu-all.h | 1 +
cutils.c | 29 ++++
docs/xbzrle.txt | 115 +++++++++++++++
exec-obsolete.h | 50 ++++---
exec.c | 34 +++--
hmp-commands.hx | 34 +++++
hmp.c | 90 ++++++++++++
hmp.h | 3 +
include/qemu/cache.h | 81 +++++++++++
migration.c | 131 +++++++++++++++--
migration.h | 30 +++-
monitor.c | 7 +
qapi-schema.json | 97 ++++++++++++-
qemu-common.h | 19 +++
qmp-commands.hx | 99 +++++++++++++
savevm.c | 115 ++++++++++++++-
sysemu.h | 3 +-
trace-events | 5 +
vmstate.h | 2 +-
23 files changed, 1449 insertions(+), 102 deletions(-)
create mode 100644 cache.c
create mode 100644 docs/xbzrle.txt
create mode 100644 include/qemu/cache.h