Currently, a "period" in the RAM migration logic is at least a second
long and accounts for what happened since the last period (or the
beginning of the migration). The dirty_pages_rate counter is calculated
at the end this logic.
If the auto convergence capability is enabled from the start of the
migration, it won't be able to use this counter the first time around.
This calculates dirty_pages_rate as soon as a period is deemed over,
which allows for it to be used immediately.
Signed-off-by: Felipe Franciosi <felipe@nutanix.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
The first time migration_bitmap_sync() is called, bytes_xfer_prev is set
to ram_state.bytes_transferred which is, at this point, zero. The next
time migration_bitmap_sync() is called, an iteration has happened and
bytes_xfer_prev is set to 'x' bytes. Most likely, more than one second
has passed, so the auto converge logic will be triggered and
bytes_xfer_now will also be set to 'x' bytes.
This condition is currently masked by dirty_rate_high_cnt, which will
wait for a few iterations before throttling. It would otherwise always
assume zero bytes have been copied and therefore throttle the guest
(possibly) prematurely.
Given bytes_xfer_prev is only used by the auto convergence logic, it
makes sense to only set its value after a check has been made against
bytes_xfer_now.
Signed-off-by: Felipe Franciosi <felipe@nutanix.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Unfortunately it's legal to create a VM with a RAM size that's
not a multiple of the underlying host page or huge page size.
Recently I'd changed things to always send host sized pages,
and that breaks if we have say a 1025MB guest on 2MB hugepages.
Unfortunately we can't just make that illegal since it would break
migration from/to existing oddly configured VMs.
Symptom: qemu-system-x86_64: Illegal RAM offset 40100000
as it transmits the fraction of the hugepage after the end
of the RAMBlock (may also cause a crash on the source
- possibly due to clearing bits after the bitmap)
Reported-by: Yumei Huang <yuhuang@redhat.com>
Red Hat bug: https://bugzilla.redhat.com/show_bug.cgi?id=1449037
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>
HMP pull
# gpg: Signature made Wed 17 May 2017 07:03:39 PM BST
# gpg: using RSA key 0x0516331EBC5BFDE7
# gpg: Good signature from "Dr. David Alan Gilbert (RH2) <dgilbert@redhat.com>"
# gpg: WARNING: This key is not certified with a trusted signature!
# gpg: There is no indication that the signature belongs to the owner.
# Primary key fingerprint: 45F5 C71B 4A0C B7FB 977A 9FA9 0516 331E BC5B FDE7
* dgilbert/tags/pull-hmp-20170517:
ramblock: add new hmp command "info ramblock"
utils: provide size_to_str()
ramblock: add RAMBLOCK_FOREACH()
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reflects better what it does now, and avoid confussions with
RAM_SAVE_FLAG_COMPRESS_PAGE.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Compression threads got broken on commit
commit 2479569466
Author: Juan Quintela <quintela@redhat.com>
Date: Tue Mar 21 11:45:01 2017 +0100
ram: reorganize last_sent_block
On do_compress_ram_page() we use a different QEMUFile than the
migration one. We need to pass it there. The failure can be seen as:
(qemu) qemu-system-x86_64: Unknown combination of migration flags: 0
qemu-system-x86_64: error while loading state section id 3(ram)
qemu-system-x86_64: load of migration failed: Invalid argument
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Tested-by: Peter Xu <peterx@redhat.com>
A couple more traces that would have made fixing that postcopy
bug a bit easier.
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>
It is internal to migration, not intended for other users.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Both the ram bitmap and the unsent bitmap are split by RAMBlock.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: zhanghailiang <zhang.zhanghailiang@huawei.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
--
Fix compilation when DEBUG_POSTCOPY is enabled (thanks Hailiang)
This removes the needto pass also the absolute offset.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
We are moving everything to work on pages, not addresses.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
We use an unsigned long for the page number. Notice that our bitmaps
already got that for the index, so we have that limit.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
--
rename page to page_abs everywhere.
fix trace types for pages
We were setting it far away of when we changed it. Now everything is
done inside save_page_header. Once there, reorganize code to pass
RAMState. We also set CONTINUE flag in a single place.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
We change the meaning of start to be the offset from the beggining of
the block.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
We need to call for the migrate_get_current() in more that half of the
uses, so call that inside.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
We can calculate its value, so we don't create a variable for it.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
--
After Peter and Dave review, I dropped the variable and just inlined
the condition.
Fix typo
We receive the file from save_live operations and we don't use it
until 3 or 4 levels of calls down.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Treat it like the rest of ram stats counters. Export its value the
same way. As an added bonus, no more MigrationState used in
migration_bitmap_sync();
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
--
Again, dave was the one reviewing it
It can be recalculated from dirty_pages_rate.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
--
Dave was the one that reviewed it O:-)
This is a ram field that was inside MigrationState. Move it to
RAMState and make it the same that the other ram stats.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
This are the last postcopy fields still at MigrationState. Once there
Move MigrationSrcPageRequest to ram.c and remove MigrationState
parameters where appropiate.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
It was on MigrationState when it is only used inside ram.c for
postcopy. Problem is that we need to access it without being able to
pass it RAMState directly.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Just unfold it. Move ram_bytes_remaining() with the rest of exported
functions.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Its value can be calculated by other exported.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
For compatibility, we need to still send a value, but just specify it
and comment the fact.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
