* zhanghailiang (zhang.zhanghaili...@huawei.com) wrote:
> On 2015/11/14 2:34, Dr. David Alan Gilbert wrote:
> >* zhanghailiang (zhang.zhanghaili...@huawei.com) wrote:
> >>Do checkpoint periodically, the default interval is 200ms.
> >>
> >>Signed-off-by: zhanghailiang <zhang.zhanghaili...@huawei.com>
> >>Signed-off-by: Li Zhijian <lizhij...@cn.fujitsu.com>
> >>---
> >> migration/colo.c | 14 ++++++++++++++
> >> 1 file changed, 14 insertions(+)
> >>
> >>diff --git a/migration/colo.c b/migration/colo.c
> >>index 0efab21..a6791f4 100644
> >>--- a/migration/colo.c
> >>+++ b/migration/colo.c
> >>@@ -11,12 +11,19 @@
> >> */
> >>
> >> #include <unistd.h>
> >>+#include "qemu/timer.h"
> >> #include "sysemu/sysemu.h"
> >> #include "migration/colo.h"
> >> #include "trace.h"
> >> #include "qemu/error-report.h"
> >> #include "qemu/sockets.h"
> >>
> >>+/*
> >>+ * checkpoint interval: unit ms
> >>+ * Note: Please change this default value to 10000 when we support hybrid
> >>mode.
> >>+ */
> >>+#define CHECKPOINT_MAX_PEROID 200
> >
> >Why not put the patch that makes this a configurable parameter before this,
> >and then we can use it straight away?
> >
>
> Do you mean setting this value by command "migrate_set_parameter" ?
> I have realized it in patch 26.
Yes, I mean reorder the patch series; put the migrate_set_parameter addition
before this patch, and then use it straight away.
Dave
> >> /* colo buffer */
> >> #define COLO_BUFFER_BASE_SIZE (4 * 1024 * 1024)
> >>
> >>@@ -183,6 +190,7 @@ out:
> >> static void colo_process_checkpoint(MigrationState *s)
> >> {
> >> QEMUSizedBuffer *buffer = NULL;
> >>+ int64_t current_time, checkpoint_time =
> >>qemu_clock_get_ms(QEMU_CLOCK_HOST);
> >> int fd, ret = 0;
> >>
> >> /* Dup the fd of to_dst_file */
> >>@@ -220,11 +228,17 @@ static void colo_process_checkpoint(MigrationState *s)
> >> trace_colo_vm_state_change("stop", "run");
> >>
> >> while (s->state == MIGRATION_STATUS_COLO) {
> >>+ current_time = qemu_clock_get_ms(QEMU_CLOCK_HOST);
> >>+ if (current_time - checkpoint_time < CHECKPOINT_MAX_PEROID) {
> >>+ g_usleep(100000);
> >>+ continue;
> >>+ }
> >
> >I'm a bit concerned at the 100ms wait, when the period is 200ms;
> >depending how the times work out, couldn't we end up waiting for just
> >under 300ms? - that's a big error - and it's even more weird when
> >we make it configurable later.
> >
>
> Agreed.
>
> >I don't think we've got a sleep-until, which is a shame; but how
> >about something like:
> >
> > if (current_time - checkpoint_time < CHECKPOINT_MAX_PEROID) {
> > int64_t delay_ms;
> > delay_ms = CHECKPOINT_MAX_PERIOD - (current_time - checkpoint_time);
> > g_usleep (delay_ms * 1000);
> > }
> >
>
> That's a reasonable modification. I will fix it like that in next version.
>
> Thanks，
> zhanghailiang
>
> >Dave
> >
> >> /* start a colo checkpoint */
> >> ret = colo_do_checkpoint_transaction(s, buffer);
> >> if (ret < 0) {
> >> goto out;
> >> }
> >>+ checkpoint_time = qemu_clock_get_ms(QEMU_CLOCK_HOST);
> >> }
> >>
> >> out:
> >>--
> >>1.8.3.1
> >>
> >>
> >--
> >Dr. David Alan Gilbert / dgilb...@redhat.com / Manchester, UK
> >
> >.
> >
>
>
--
Dr. David Alan Gilbert / dgilb...@redhat.com / Manchester, UK
