Peter Xu <pet...@redhat.com> wrote:
> On Thu, Mar 23, 2017 at 09:45:04PM +0100, Juan Quintela wrote:
>> Once there rename it to its actual meaning, zero_pages.
>>
>> Signed-off-by: Juan Quintela <quint...@redhat.com>
>> Reviewed-by: Dr. David Alan Gilbert <dgilb...@redhat.com>
>
> Reviewed-by: Peter Xu <pet...@redhat.com>
>
> Will post a question below though (not directly related to this patch
> but context-wide)...
>> {
>> int pages = -1;
>>
>> if (is_zero_range(p, TARGET_PAGE_SIZE)) {
>> - acct_info.dup_pages++;
>> + rs->zero_pages++;
>> *bytes_transferred += save_page_header(f, block,
>> offset |
>> RAM_SAVE_FLAG_COMPRESS);
>> qemu_put_byte(f, 0);
>> @@ -822,11 +826,11 @@ static int ram_save_page(RAMState *rs, MigrationState
>> *ms, QEMUFile *f,
>> if (bytes_xmit > 0) {
>> acct_info.norm_pages++;
>> } else if (bytes_xmit == 0) {
>> - acct_info.dup_pages++;
>> + rs->zero_pages++;
>
> This code path looks suspicous... since iiuc currently it should only
> be triggered by RDMA case, and I believe here qemu_rdma_save_page()
> should have met something wrong (so that it didn't return with
> RAM_SAVE_CONTROL_DELAYED). Then is it correct we do increase zero page
> counting unconditionally here? (hmm, the default bytes_xmit is zero as
> well...)
My head hurts at this point.
ok. bytse_xmit can only be zero if we called qemu_rdma_save_page() with
size=0 or there has been an RDMA error. We ver call the function with
size = 0. And if there is one error, we are in very bady shape already.
> Another thing is that I see when RDMA is enabled we are updating
> accounting info with acct_update_position(), while we updated it here
> as well. Is this an issue of duplicated accounting?
I think stats and rdma are not right. I have to check more that.
Thanks, Juan.
