The current dirtylimit_throttle_pct trace event is triggered when the
throttle time is adjusted linearly. Modify the trace event so that it
can record non-linear adjustments. Additionally, since the throttle time
might be adjusted again at the end of the dirtylimit_set_throttle
function, move the trace event to after this process and calculate the
final adjustment time and sleep percent.
This patch can fix the following issue:
1. The current dirty rate at 1000MB/s and the dirty limit value at
10000MB/s, before merge this patch, this trace event will print:
CPU[2] throttle percent: 98, throttle adjust time 191590 us
CPU[2] throttle percent: 98, throttle adjust time 191002 us
CPU[2] throttle percent: 98, throttle adjust time 191002 us
After merge this patch, there will be no print.
2. The current dirty rate is 1000MB/s and the dirty limit rate value is
333MB/s, before merge this patch, this trace event will print:
CPU[3] throttle percent: 98, throttle adjust time 32666634 us
It will only print linear adjustment, and the adjust time
will be larger and only have positive values.
After merge this patch, print as following:
CPU[2] throttle percent: 97, throttle adjust time 128766 us
CPU[2] throttle percent: 94, throttle adjust time -61131 us
CPU[2] throttle percent: 92, throttle adjust time -16634 us
...
CPU[2] throttle percent: 74, throttle adjust time -390 us
CPU[2] throttle percent: 73, throttle adjust time -390 us
Signed-off-by: wangfuqiang49 <wangfuqian...@jd.com>
---
system/dirtylimit.c | 28 ++++++++++++++++++++--------
1 file changed, 20 insertions(+), 8 deletions(-)
diff --git a/system/dirtylimit.c b/system/dirtylimit.c
index 7c071248bb..c7f663e5b9 100644
--- a/system/dirtylimit.c
+++ b/system/dirtylimit.c
@@ -281,31 +281,30 @@ static void dirtylimit_set_throttle(CPUState *cpu,
{
int64_t ring_full_time_us = 0;
uint64_t sleep_pct = 0;
+ uint64_t throttle_pct = 0;
uint64_t throttle_us = 0;
+ int64_t throtlle_us_old = cpu->throttle_us_per_full;
if (current == 0) {
cpu->throttle_us_per_full = 0;
- return;
+ goto end;
}
ring_full_time_us = dirtylimit_dirty_ring_full_time(current);
if (dirtylimit_need_linear_adjustment(quota, current)) {
if (quota < current) {
- sleep_pct = (current - quota) * 100 / current;
+ throttle_pct = (current - quota) * 100 / current;
throttle_us =
- ring_full_time_us * sleep_pct / (double)(100 - sleep_pct);
+ ring_full_time_us * throttle_pct / (double)(100 -
throttle_pct);
cpu->throttle_us_per_full += throttle_us;
} else {
- sleep_pct = (quota - current) * 100 / quota;
+ throttle_pct = (quota - current) * 100 / quota;
throttle_us =
- ring_full_time_us * sleep_pct / (double)(100 - sleep_pct);
+ ring_full_time_us * throttle_pct / (double)(100 -
throttle_pct);
cpu->throttle_us_per_full -= throttle_us;
}
- trace_dirtylimit_throttle_pct(cpu->cpu_index,
- sleep_pct,
- throttle_us);
} else {
if (quota < current) {
cpu->throttle_us_per_full += ring_full_time_us / 10;
@@ -323,6 +322,19 @@ static void dirtylimit_set_throttle(CPUState *cpu,
ring_full_time_us * DIRTYLIMIT_THROTTLE_PCT_MAX);
cpu->throttle_us_per_full = MAX(cpu->throttle_us_per_full, 0);
+
+end:
+ if (cpu->throttle_us_per_full - throtlle_us_old) {
+ if (current) {
+ sleep_pct = ring_full_time_us * 100 / (ring_full_time_us +
+ cpu->throttle_us_per_full);
+ } else {
+ sleep_pct = 0;
+ }
+ trace_dirtylimit_throttle_pct(cpu->cpu_index,
+ sleep_pct,
+ cpu->throttle_us_per_full -
+ throtlle_us_old); }
}
static void dirtylimit_adjust_throttle(CPUState *cpu)
--
2.47.0
