mirror of
https://github.com/qemu/qemu.git
synced 2026-07-08 17:46:10 +00:00
39ab94e414
Introduce this new counter to remember the total dirty bytes for the whole system. It will be used for query-migrate command to fetch system-wise remaining data. A prior attempt was made to not use this counter but query directly from all the modules in a QMP handler, but it exposed some complexity not only on migration state machine race conditions (where the query may be invoked anytime of the state machine), or on locking implications (where some of the query hooks may take BQL, which is illegal at least in a QMP handler). For more information, see: https://lore.kernel.org/r/aeZMtxqrKWAMKzdN@x1.local This oneliner will resolve everything, except that it is not as accurate. The hope is it is a worthwhile trade-off solution, after knowing above challenges. Now, there is one more reason we should make each invocation of save_live_iterate() to be lightweight, because this counter will only get updated once for each loop over all save_live_iterate() hooks when present. But that's always the goal. Reviewed-by: Juraj Marcin <jmarcin@redhat.com> Link: https://lore.kernel.org/r/20260421202110.306051-14-peterx@redhat.com Signed-off-by: Peter Xu <peterx@redhat.com>
142 lines
3.6 KiB
C
142 lines
3.6 KiB
C
/*
|
|
* Migration stats
|
|
*
|
|
* Copyright (c) 2012-2023 Red Hat Inc
|
|
*
|
|
* Authors:
|
|
* Juan Quintela <quintela@redhat.com>
|
|
*
|
|
* This work is licensed under the terms of the GNU GPL, version 2 or later.
|
|
* See the COPYING file in the top-level directory.
|
|
*/
|
|
|
|
#ifndef QEMU_MIGRATION_STATS_H
|
|
#define QEMU_MIGRATION_STATS_H
|
|
|
|
/*
|
|
* Amount of time to allocate to each "chunk" of bandwidth-throttled
|
|
* data.
|
|
*/
|
|
#define BUFFER_DELAY 100
|
|
|
|
/*
|
|
* If rate_limit_max is 0, there is special code to remove the rate
|
|
* limit.
|
|
*/
|
|
#define RATE_LIMIT_DISABLED 0
|
|
|
|
/*
|
|
* These are the ram migration statistic counters. It is loosely
|
|
* based on MigrationRAMStats.
|
|
*/
|
|
typedef struct {
|
|
/*
|
|
* Number of bytes that were reported dirty after the latest
|
|
* system-wise synchronization of dirty information. It is used to do
|
|
* best-effort estimation on expected downtime.
|
|
*/
|
|
uint64_t dirty_bytes_last_sync;
|
|
/*
|
|
* Number of bytes that were reported dirty now. This is an estimate
|
|
* value and will be updated every time migration thread queries from
|
|
* modules in an iteration loop. It is used to provide best-effort
|
|
* estimation on total remaining data.
|
|
*/
|
|
uint64_t dirty_bytes_total;
|
|
/*
|
|
* Number of pages dirtied per second.
|
|
*/
|
|
uint64_t dirty_pages_rate;
|
|
/*
|
|
* Number of times we have synchronized guest bitmaps. This always
|
|
* starts from 1 for the 1st iteration.
|
|
*/
|
|
uint64_t dirty_sync_count;
|
|
/*
|
|
* Number of times zero copy failed to send any page using zero
|
|
* copy.
|
|
*/
|
|
uint64_t dirty_sync_missed_zero_copy;
|
|
/*
|
|
* Number of bytes sent at migration completion stage while the
|
|
* guest is stopped.
|
|
*/
|
|
uint64_t downtime_bytes;
|
|
/*
|
|
* Number of bytes sent through multifd channels.
|
|
*/
|
|
uint64_t multifd_bytes;
|
|
/*
|
|
* Number of pages transferred that were not full of zeros.
|
|
*/
|
|
uint64_t normal_pages;
|
|
/*
|
|
* Number of bytes sent during postcopy.
|
|
*/
|
|
uint64_t postcopy_bytes;
|
|
/*
|
|
* Number of postcopy page faults that we have handled during
|
|
* postcopy stage.
|
|
*/
|
|
uint64_t postcopy_requests;
|
|
/*
|
|
* Number of bytes sent during precopy stage.
|
|
*/
|
|
uint64_t precopy_bytes;
|
|
/*
|
|
* Number of bytes transferred with QEMUFile.
|
|
*/
|
|
uint64_t qemu_file_transferred;
|
|
/*
|
|
* Amount of transferred data at the start of current cycle.
|
|
*/
|
|
uint64_t rate_limit_start;
|
|
/*
|
|
* Maximum amount of data we can send in a cycle.
|
|
*/
|
|
uint64_t rate_limit_max;
|
|
/*
|
|
* Number of bytes sent through RDMA.
|
|
*/
|
|
uint64_t rdma_bytes;
|
|
/*
|
|
* Number of pages transferred that were full of zeros.
|
|
*/
|
|
uint64_t zero_pages;
|
|
} MigrationAtomicStats;
|
|
|
|
extern MigrationAtomicStats mig_stats;
|
|
|
|
/**
|
|
* migration_rate_get: Get the maximum amount that can be transferred.
|
|
*
|
|
* Returns the maximum number of bytes that can be transferred in a cycle.
|
|
*/
|
|
uint64_t migration_rate_get(void);
|
|
|
|
/**
|
|
* migration_rate_reset: Reset the rate limit counter.
|
|
*
|
|
* This is called when we know we start a new transfer cycle.
|
|
*/
|
|
void migration_rate_reset(void);
|
|
|
|
/**
|
|
* migration_rate_set: Set the maximum amount that can be transferred.
|
|
*
|
|
* Sets the maximum amount of bytes that can be transferred in one cycle.
|
|
*
|
|
* @new_rate: new maximum amount
|
|
*/
|
|
void migration_rate_set(uint64_t new_rate);
|
|
|
|
/**
|
|
* migration_transferred_bytes: Return number of bytes transferred
|
|
*
|
|
* Returns how many bytes have we transferred since the beginning of
|
|
* the migration. It accounts for bytes sent through any migration
|
|
* channel, multifd, qemu_file, rdma, ....
|
|
*/
|
|
uint64_t migration_transferred_bytes(void);
|
|
#endif
|