qemu/migration/migration-stats.c
Juan Quintela 737840e2c6 migration: Use the number of transferred bytes directly
We only use migration_transferred_bytes() to calculate the rate_limit,
for that we don't need to flush whatever is on the qemu_file buffer.
Remember that the buffer is really small (normal case is 32K if we use
iov's can be 64 * TARGET_PAGE_SIZE), so this is not relevant to
calculations.

Reviewed-by: Fabiano Rosas <farosas@suse.de>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Message-ID: <20231025091117.6342-5-quintela@redhat.com>
2023-10-31 08:44:33 +01:00

71 lines
1.7 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.
*/
#include "qemu/osdep.h"
#include "qemu/stats64.h"
#include "qemu-file.h"
#include "trace.h"
#include "migration-stats.h"
MigrationAtomicStats mig_stats;
bool migration_rate_exceeded(QEMUFile *f)
{
if (qemu_file_get_error(f)) {
return true;
}
uint64_t rate_limit_max = migration_rate_get();
if (rate_limit_max == RATE_LIMIT_DISABLED) {
return false;
}
uint64_t rate_limit_start = stat64_get(&mig_stats.rate_limit_start);
uint64_t rate_limit_current = migration_transferred_bytes(f);
uint64_t rate_limit_used = rate_limit_current - rate_limit_start;
if (rate_limit_max > 0 && rate_limit_used > rate_limit_max) {
return true;
}
return false;
}
uint64_t migration_rate_get(void)
{
return stat64_get(&mig_stats.rate_limit_max);
}
#define XFER_LIMIT_RATIO (1000 / BUFFER_DELAY)
void migration_rate_set(uint64_t limit)
{
/*
* 'limit' is per second. But we check it each BUFFER_DELAY milliseconds.
*/
stat64_set(&mig_stats.rate_limit_max, limit / XFER_LIMIT_RATIO);
}
void migration_rate_reset(QEMUFile *f)
{
stat64_set(&mig_stats.rate_limit_start, migration_transferred_bytes(f));
}
uint64_t migration_transferred_bytes(QEMUFile *f)
{
uint64_t multifd = stat64_get(&mig_stats.multifd_bytes);
uint64_t rdma = stat64_get(&mig_stats.rdma_bytes);
uint64_t qemu_file = stat64_get(&mig_stats.qemu_file_transferred);
trace_migration_transferred_bytes(qemu_file, multifd, rdma);
return qemu_file + multifd + rdma;
}