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path: root/include/migration/migration.h
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2015-08-03migration: Fix global state with Xen.Anthony PERARD
When doing migration via the QMP command xen_save_devices_state, the current runstate is not store into the global state section. Also the current runstate is not the one we want on the receiver side. During migration, the Xen toolstack paused QEMU before save the devices state. Also, the toolstack expect QEMU to autostart when the migration is finished. So this patch store "running" as it's current runstate. Signed-off-by: Anthony PERARD <anthony.perard@citrix.com> Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
2015-07-15migration: We also want to store the global state for savevmJuan Quintela
Commit df4b1024526cae3479da3492d6371fd4a7324a03 introduced global_state section. But it only filled the state while doing migration. While doing a savevm, we stored an empty string as state. So when we did a loadvm, it complained that state was invalid. Fedora 21, 4.1.1, qemu 2.4.0-rc0 > ../../configure --target-list="x86_64-softmmu" 068 2s ... - output mismatch (see 068.out.bad) --- /home/bos/jhuston/src/qemu/tests/qemu-iotests/068.out 2015-07-08 17:56:18.588164979 -0400 +++ 068.out.bad 2015-07-09 17:39:58.636651317 -0400 @@ -6,6 +6,8 @@ QEMU X.Y.Z monitor - type 'help' for more information (qemu) savevm 0 (qemu) quit +qemu-system-x86_64: Unknown savevm section or instance 'globalstate' 0 +qemu-system-x86_64: Error -22 while loading VM state QEMU X.Y.Z monitor - type 'help' for more information (qemu) quit *** done Failures: 068 Failed 1 of 1 tests Actually, there were two problems here: - we registered global_state too late for load_vm (fixed on another patch on the list) - we didn't store a valid state for savevm (fixed by this patch). Reported-by: John Snow <jsnow@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Reviewed-by: Amit Shah <amit.shah@redhat.com> Tested-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-07-07migration: Make events a capabilityJuan Quintela
Make check fails with events. THis is due to the parser/lexer that it uses. Just in case that they are more broken parsers, just only send events when there are capabilities. Signed-off-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2015-07-07migration: Add configuration sectionJuan Quintela
It needs to be the first one and it is not optional, that is the reason why it is opencoded. For new machine types, it is required that machine type name is the same in both sides. It is just done right now for pc's. Signed-off-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2015-07-07global_state: Make section optionalJuan Quintela
This section would be sent: a- for all new machine types b- for old machine types if section state is different form {running,paused} that were the only giving us troubles. So, in new qemus: it is alwasy there. In old qemus: they are only there if it an error has happened, basically stoping on target. Signed-off-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2015-07-07migration: create new section to store global stateJuan Quintela
This includes a new section that for now just stores the current qemu state. Right now, there are only one way to control what is the state of the target after migration. - If you run the target qemu with -S, it would start stopped. - If you run the target qemu without -S, it would run just after migration finishes. The problem here is what happens if we start the target without -S and there happens one error during migration that puts current state as -EIO. Migration would ends (notice that the error happend doing block IO, network IO, i.e. nothing related with migration), and when migration finish, we would just "continue" running on destination, probably hanging the guest/corruption data, whatever. Signed-off-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2015-07-07Rework ram_control_load_hook to hook during block loadDr. David Alan Gilbert
We need the names of RAMBlocks as they're loaded for RDMA, reuse a slightly modified ram_control_load_hook: a) Pass a 'data' parameter to use for the name in the block-reg case b) Only some hook types now require the presence of a hook function. Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2015-06-12Add a protective section footerDr. David Alan Gilbert
Badly formatted migration streams can go undetected or produce misleading errors due to a lock of checking at the end of sections. In particular a section that adds an extra 0x00 at the end causes what looks like a normal end of stream and thus doesn't produce any errors, and something that ends in a 0x01..0x04 kind of look like real section headers and then fail when the section parser tries to figure out which section they are. This is made worse by the choice of 0x00..0x04 being small numbers that are particularly common in normal section data. This patch adds a section footer consisting of a marker (0x7e - ~) followed by the section-id that was also sent in the header. If they mismatch then it throws an error explaining which section was being loaded. 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>
2015-06-12Disable section footers on older machine typesDr. David Alan Gilbert
The next patch adds section footers; but we don't want to break migration compatibility so disable them on older machine types 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>
2015-06-12Move loadvm_handlers into MigrationIncomingStateDr. David Alan Gilbert
In postcopy we need the loadvm_handlers to be used in a couple of different instances of the loadvm loop/routine, and thus it can't be local any more. Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Reviewed-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2015-06-12Create MigrationIncomingStateDr. David Alan Gilbert
There are currently lots of pieces of incoming migration state scattered around, and postcopy is adding more, and it seems better to try and keep it together. allocate MIS in process_incoming_migration_co Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Reviewed-by: Amit Shah <amit.shah@redhat.com> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Reviewed-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2015-06-12migration: move ram stuff to migration/ramJuan Quintela
For historic reasons, ram migration have been on arch_init.c. Just split it into migration/ram.c, the same that happened with block.c. There is only code movement, no changes altogether. Signed-off-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com>
2015-05-07migration: Use an array instead of 3 parametersLiang Li
Put the three parameters related to multiple thread (de)compression into an int array, and use an enum type to index the parameter. Signed-off-by: Liang Li <liang.z.li@intel.com> Signed-off-by: Yang Zhang <yang.z.zhang@intel.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2015-05-06migration: Add the framework of multi-thread decompressionLiang Li
Add the code to create and destroy the multiple threads those will be used to do data decompression. Left some functions empty just to keep clearness, and the code will be added later. Signed-off-by: Liang Li <liang.z.li@intel.com> Signed-off-by: Yang Zhang <yang.z.zhang@intel.com> Reviewed-by: Dr.David Alan Gilbert <dgilbert@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2015-05-06migration: Add the framework of multi-thread compressionLiang Li
Add the code to create and destroy the multiple threads those will be used to do data compression. Left some functions empty to keep clearness, and the code will be added later. Signed-off-by: Liang Li <liang.z.li@intel.com> Signed-off-by: Yang Zhang <yang.z.zhang@intel.com> Reviewed-by: Dr.David Alan Gilbert <dgilbert@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2015-03-17migration: Remove unused functionsThomas Huth
migrate_rdma_pin_all() and qsb_clone() are completely unused and thus can be deleted. Signed-off-by: Thomas Huth <thuth@linux.vnet.ibm.com> Cc: Juan Quintela <quintela@redhat.com> Cc: Amit Shah <amit.shah@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2015-03-16ram: make all save_page functions take a uint64_t parameterJuan Quintela
It used to be an int, but then we can't pass directly the bytes_transferred parameter, that would happen later in the series. Signed-off-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Amit Shah <amit.shah@redhat.com>
2015-02-18hmp: Clean up declarations for long-gone info handlersMarkus Armbruster
Leftovers from d1f2964 qapi: Convert query-spice 791e7c8 qapi: Convert query-migrate 0fe6a7f slirp: Drop statistic code Signed-off-by: Markus Armbruster <armbru@redhat.com>
2015-02-05migration: Append JSON description of migration streamAlexander Graf
One of the annoyances of the current migration format is the fact that it's not self-describing. In fact, it's not properly describing at all. Some code randomly scattered throughout QEMU elaborates roughly how to read and write a stream of bytes. We discussed an idea during KVM Forum 2013 to add a JSON description of the migration protocol itself to the migration stream. This patch adds a section after the VM_END migration end marker that contains description data on what the device sections of the stream are composed of. This approach is backwards compatible with any QEMU version reading the stream, because QEMU just stops reading after the VM_END marker and ignores any data following it. With an additional external program this allows us to decipher the contents of any migration stream and hopefully make migration bugs easier to track down. Signed-off-by: Alexander Graf <agraf@suse.de> Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2014-05-05migration: expose xbzrle cache miss rateChenLiang
expose xbzrle cache miss rate Signed-off-by: ChenLiang <chenliang88@huawei.com> Signed-off-by: Gonglei <arei.gonglei@huawei.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2014-05-05migration: expose the bitmap_sync_count to the endChenLiang
expose the count that logs the times of updating the dirty bitmap to end user. Signed-off-by: ChenLiang <chenliang88@huawei.com> Signed-off-by: Gonglei <arei.gonglei@huawei.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2014-05-05Provide init function for ram migrationDr. David Alan Gilbert
Provide ram_mig_init (like blk_mig_init) for vl.c to initialise stuff to do with ram migration (currently in arch_init.c). Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Reviewed-by: Gonglei <arei.gonglei@huawei.com> Reviewed-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2014-02-04migration:fix free XBZRLE decoded_buf wrongGonglei (Arei)
When qemu do live migration with xbzrle, qemu malloc decoded_buf at destination end but free it at source end. It will crash qemu by double free error in some scenarios. Splitting the XBZRLE structure for clear logic distinguishing src/dst side. Signed-off-by: ChenLiang <chenliang88@huawei.com> Reviewed-by: Peter Maydell <peter.maydell@linaro.org> Reviewed-by: Orit Wasserman <owasserm@redhat.com> Signed-off-by: GongLei <arei.gonglei@huawei.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2014-01-13migration: Move QEMU_VM_* defines to migration/migration.hEduardo Habkost
The VMState code will be moved to vmstate.c and it uses some of the QEMU_VM_* constants, so move it to a header. Signed-off-by: Eduardo Habkost <ehabkost@redhat.com> Reviewed-by: Orit Wasserman <owasserm@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2013-07-29migration: fix spice migrationStefan Hajnoczi
Commit 29ae8a4133082e16970c9d4be09f4b6a15034617 ("rdma: introduce MIG_STATE_NONE and change MIG_STATE_SETUP state transition") changed the state transitions during migration setup. Spice used to be notified with MIG_STATE_ACTIVE and it detected this using migration_is_active(). Spice is now notified with MIG_STATE_SETUP and migration_is_active() no longer works. Replace migration_is_active() with migration_in_setup() to fix spice migration. Cc: Michael R. Hines <mrhines@us.ibm.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-07-23rdma: account for the time spent in MIG_STATE_SETUP through QMPMichael R. Hines
Using the previous patches, we're now able to timestamp the SETUP state. Once we have this time, let the user know about it in the schema. Reviewed-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Michael R. Hines <mrhines@us.ibm.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2013-07-23rdma: core logicMichael R. Hines
Code that does need to be visible is kept well contained inside this file and this is the only new additional file to the entire patch. This file includes the entire protocol and interfaces required to perform RDMA migration. Also, the configure and Makefile modifications to link this file are included. Full documentation is in docs/rdma.txt Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Chegu Vinod <chegu_vinod@hp.com> Tested-by: Chegu Vinod <chegu_vinod@hp.com> Tested-by: Michael R. Hines <mrhines@us.ibm.com> Signed-off-by: Michael R. Hines <mrhines@us.ibm.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2013-07-23rdma: introduce ram_handle_compressed()Michael R. Hines
This gives RDMA shared access to madvise() on the destination side when an entire chunk is found to be zero. Reviewed-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Chegu Vinod <chegu_vinod@hp.com> Tested-by: Chegu Vinod <chegu_vinod@hp.com> Tested-by: Michael R. Hines <mrhines@us.ibm.com> Signed-off-by: Michael R. Hines <mrhines@us.ibm.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2013-07-19block-migration: efficiently encode zero blocksPeter Lieven
this patch adds a efficient encoding for zero blocks by adding a new flag indicating a block is completely zero. additionally bdrv_write_zeros() is used at the destination to efficiently write these zeroes. depending on the implementation this avoids that the destination target gets fully provisioned. Signed-off-by: Peter Lieven <pl@kamp.de> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-07-12Add 'auto-converge' migration capabilityChegu Vinod
The auto-converge migration capability allows the user to specify if they choose live migration seqeunce to automatically detect and force convergence. Signed-off-by: Chegu Vinod <chegu_vinod@hp.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2013-06-27rdma: introduce capability x-rdma-pin-allMichael R. Hines
This capability allows you to disable dynamic chunk registration for better throughput on high-performance links. For example, using an 8GB RAM virtual machine with all 8GB of memory in active use and the VM itself is completely idle using a 40 gbps infiniband link: 1. x-rdma-pin-all disabled total time: approximately 7.5 seconds @ 9.5 Gbps 2. x-rdma-pin-all enabled total time: approximately 4 seconds @ 26 Gbps These numbers would of course scale up to whatever size virtual machine you have to migrate using RDMA. Enabling this feature does *not* have any measurable affect on migration *downtime*. This is because, without this feature, all of the memory will have already been registered already in advance during the bulk round and does not need to be re-registered during the successive iteration rounds. Reviewed-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Chegu Vinod <chegu_vinod@hp.com> Reviewed-by: Eric Blake <eblake@redhat.com> Tested-by: Chegu Vinod <chegu_vinod@hp.com> Tested-by: Michael R. Hines <mrhines@us.ibm.com> Signed-off-by: Michael R. Hines <mrhines@us.ibm.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2013-06-27rdma: new QEMUFileOps hooksMichael R. Hines
These are the prototypes and implementation of new hooks that RDMA takes advantage of to perform dynamic page registration. An optional hook is also introduced for a custom function to be able to override the default save_page function. Also included are the prototypes and accessor methods used by arch_init.c which invoke funtions inside savevm.c to call out to the hooks that may or may not have been overridden inside of QEMUFileOps. Reviewed-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Chegu Vinod <chegu_vinod@hp.com> Tested-by: Chegu Vinod <chegu_vinod@hp.com> Tested-by: Michael R. Hines <mrhines@us.ibm.com> Signed-off-by: Michael R. Hines <mrhines@us.ibm.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2013-06-27rdma: export throughput w/ MigrationStats QMPMichael R. Hines
This exposes throughput (in megabits/sec) through QMP. Reviewed-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Chegu Vinod <chegu_vinod@hp.com> Tested-by: Chegu Vinod <chegu_vinod@hp.com> Tested-by: Michael R. Hines <mrhines@us.ibm.com> Signed-off-by: Michael R. Hines <mrhines@us.ibm.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2013-06-27rdma: introduce qemu_update_position()Michael R. Hines
RDMA writes happen asynchronously, and thus the performance accounting also needs to be able to occur asynchronously. This allows anybody to call into savevm.c to update both f->pos as well as into arch_init.c to update the acct_info structure with up-to-date values when the RDMA transfer actually completes. Reviewed-by: Juan Quintela <quintela@redhat.com> Tested-by: Chegu Vinod <chegu_vinod@hp.com> Tested-by: Michael R. Hines <mrhines@us.ibm.com> Signed-off-by: Michael R. Hines <mrhines@us.ibm.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2013-03-26migration: do not sent zero pages in bulk stagePeter Lieven
during bulk stage of ram migration if a page is a zero page do not send it at all. the memory at the destination reads as zero anyway. even if there is an madvise with QEMU_MADV_DONTNEED at the target upon receipt of a zero page I have observed that the target starts swapping if the memory is overcommitted. it seems that the pages are dropped asynchronously. this patch also updates QMP to return the number of skipped pages in MigrationStats. Signed-off-by: Peter Lieven <pl@kamp.de> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2013-03-11migration: eliminate s->migration_filePaolo Bonzini
The indirection is useless now. Backends can open s->file directly. Reviewed-by: Orit Wasserman <owasserm@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2013-03-11migration: use QEMUFile for writing outgoing migration dataPaolo Bonzini
Second, drop the file descriptor indirection, and write directly to the QEMUFile. Reviewed-by: Orit Wasserman <owasserm@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2013-03-11migration: use QEMUFile for migration channel lifetimePaolo Bonzini
As a start, use QEMUFile to store the destination and close it. qemu_get_fd gets a file descriptor that will be used by the write callbacks. Reviewed-by: Orit Wasserman <owasserm@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2013-03-11migration: yay, buffering is gonePaolo Bonzini
Buffering was needed because blocking writes could take a long time and starve other threads seeking to grab the big QEMU mutex. Now that all writes (except within _complete callbacks) are done outside the big QEMU mutex, we do not need buffering at all. Reviewed-by: Orit Wasserman <owasserm@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2013-03-11migration: cleanup migration (including thread) in the iothreadPaolo Bonzini
Perform final cleanup in a bottom half, and add joining the thread to the series of cleanup actions. migrate_fd_error remains for connection error, but it doesn't need to cleanup anything anymore. Reviewed-by: Orit Wasserman <owasserm@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2013-03-11migration: simplify error handlingPaolo Bonzini
Always use qemu_file_get_error to detect errors, since that is how QEMUFile itself drops I/O after an error occurs. There is no need to propagate and check return values all the time. Also remove the "complete" member, since we know that it is set (via migrate_fd_cleanup) only when the state changes. Reviewed-by: Orit Wasserman <owasserm@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2013-02-22migration: calculate expected_downtimeJuan Quintela
We removed the calculation in commit e4ed1541ac9413eac494a03532e34beaf8a7d1c5 Now we add it back. We need to create dirty_bytes_rate because we can't include cpu-all.h from migration.c, and there is no other way to include TARGET_PAGE_SIZE. Signed-off-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Orit Wasserman <owasserm@redhat.com>
2013-01-17migration: move beginning stage to the migration threadJuan Quintela
Signed-off-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
2013-01-17migration: make function staticPaolo Bonzini
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Reviewed-by: Eric Blake <eblake@redhat.com>
2012-12-20migration: merge QEMUFileBuffered into MigrationStateJuan Quintela
Avoid splitting the state of outgoing migration, more or less arbitrarily, between two data structures. QEMUFileBuffered anyway is used only during migration. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2012-12-20migration: Inline qemu_fopen_ops_buffered into migrate_fd_connectJuan Quintela
Signed-off-by: Juan Quintela <quintela@redhat.com>
2012-12-20migration: move migration_fd_put_ready()Juan Quintela
Put it near its use and un-export it. Signed-off-by: Juan Quintela <quintela@redhat.com>
2012-12-20migration: move buffered_file.c code into migration.cJuan Quintela
This only moves the code (also from buffered_file.h to migration.h). Fix whitespace until checkpatch is happy. Signed-off-by: Juan Quintela <quintela@redhat.com>
2012-12-20savevm: New save live migration method: pendingJuan Quintela
Code just now does (simplified for clarity) if (qemu_savevm_state_iterate(s->file) == 1) { vm_stop_force_state(RUN_STATE_FINISH_MIGRATE); qemu_savevm_state_complete(s->file); } Problem here is that qemu_savevm_state_iterate() returns 1 when it knows that remaining memory to sent takes less than max downtime. But this means that we could end spending 2x max_downtime, one downtime in qemu_savevm_iterate, and the other in qemu_savevm_state_complete. Changed code to: pending_size = qemu_savevm_state_pending(s->file, max_size); DPRINTF("pending size %lu max %lu\n", pending_size, max_size); if (pending_size >= max_size) { ret = qemu_savevm_state_iterate(s->file); } else { vm_stop_force_state(RUN_STATE_FINISH_MIGRATE); qemu_savevm_state_complete(s->file); } So what we do is: at current network speed, we calculate the maximum number of bytes we can sent: max_size. Then we ask every save_live section how much they have pending. If they are less than max_size, we move to complete phase, otherwise we do an iterate one. This makes things much simpler, because now individual sections don't have to caluclate the bandwidth (it was implossible to do right from there). Signed-off-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
2012-12-20migration: remove unfreeze logicJuan Quintela
Now that we have a thread, and blocking writes, we don't need it. Signed-off-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>