[CRIU] [PATCH v3 10/12] shmem: add deduped anon shmem dumping to predump command

[Pavel Emelyanov]

On 08/11/2016 04:56 PM, Eugene Batalov wrote:
> When we track changes since last dump we don't dump not changed pages so we don't create
> duplicates of pages on each criu dump.

O_o Well, we don't create this even now.
So the patch title should rather be "Pre-dump anon shared memory"?

> This is not equal to full data deduplication but it is similar. Also "dedup" term is used
> already (ex. --auto-dedup option) in criu --help.

Exactly! The dedup in criu is taking images and punching duplicate data from
it, not ... doing something with pages RSS or SOFT_DIRTY detection :)

> 2016-08-10 16:23 GMT+03:00 Pavel Emelyanov <xemul at virtuozzo.com <mailto:xemul at virtuozzo.com>>:
> 
>     Again, why dedup?! It's about changes tracking, isn't it?
> 
>     On 08/07/2016 04:11 PM, Eugene Batalov wrote:
>     > As anon shmem dump supports dedup now
>     > we can work with it during predump.
>     >
>     > Signed-off-by: Eugene Batalov <eabatalov89 at gmail.com <mailto:eabatalov89 at gmail.com>>
>     > ---
>     >  criu/cr-dump.c | 4 ++++
>     >  1 file changed, 4 insertions(+)
>     >
>     > diff --git a/criu/cr-dump.c b/criu/cr-dump.c
>     > index 743100d..f65002b 100644
>     > --- a/criu/cr-dump.c
>     > +++ b/criu/cr-dump.c
>     > @@ -1563,6 +1563,10 @@ int cr_pre_dump_tasks(pid_t pid)
>     >               if (pre_dump_one_task(item))
>     >                       goto err;
>     >
>     > +     ret = cr_dump_shmem();
>     > +     if (ret)
>     > +             goto err;
>     > +
>     >       if (irmap_predump_prep())
>     >               goto err;
>     >
>     >
> 
> 
> 
> 
> -- 
> Best regards,
> Eugene Batalov.