qemu/include/migration
Dr. David Alan Gilbert f952710757 Postcopy: Mark nohugepage before discard
Prior to servicing userfault requests we must ensure we've not got
huge pages in the area that might include non-transferred memory,
since a hugepage could incorrectly mark the whole huge page as present.

We mark the area as non-huge page (nhp) just before we perform
discards; the discard code now tells us to discard any areas
that haven't been sent (as well as any that are redirtied);
any already formed transparent-huge-pages get fragmented
by this discard process if they cotnain any discards.

Transparent huge pages that have been entirely transferred
and don't contain any discards are not broken by this mechanism;
they stay as huge pages.

By starting postcopy after a full precopy pass, many of the pages
then stay as huge pages; this is important for maintaining performance
after the end of the migration.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2015-11-10 15:00:28 +01:00
..
block.h
migration.h Start up a postcopy/listener thread ready for incoming page data 2015-11-10 15:00:28 +01:00
page_cache.h xbzrle: optimize XBZRLE to decrease the cache misses 2015-01-15 17:49:43 +05:30
postcopy-ram.h Postcopy: Mark nohugepage before discard 2015-11-10 15:00:28 +01:00
qemu-file.h Return path: Open a return path on QEMUFile for sockets 2015-11-10 14:51:49 +01:00
vmstate.h Add qemu_savevm_state_complete_postcopy 2015-11-10 15:00:27 +01:00