Tejus GK <[email protected]> writes: > Currently, the dirty-sync-missed-zero-copy stat is incremented only when > an entire batch of IO operations fails to use zerocopy and falls back to > a normal copy. As long as at least one IO in the batch is successfully > zero-copied, the whole batch is treated as a success. This hides > individual IO fallbacks and makes the migration stat less accurate than > it could be. > > Make the stat more accurate by reporting at a finer granularity, i.e, by > incrementing for every individual IO fallback that occurs. > > Suggested-by: Peter Xu <[email protected]> > Signed-off-by: Tejus GK <[email protected]>
[...] > diff --git a/qapi/migration.json b/qapi/migration.json > index f925e5541b..94977b8810 100644 > --- a/qapi/migration.json > +++ b/qapi/migration.json > @@ -58,8 +58,7 @@ > # (since 7.0). > # > # @dirty-sync-missed-zero-copy: Number of times dirty RAM > -# synchronization could not avoid copying dirty pages. This is > -# between 0 and @dirty-sync-count * @multifd-channels. > +# synchronization could not avoid copying dirty pages. > # (since 7.1) > # > # Since: 0.14 Dropping the documented upper limit might make the value harder to interpret. Thus my question: how is this value to be used?
