under heavy workloads,irq_coalesced could up to 30+,
after modification EXTERNAL_INTERRUPT reduce by 40%
before:
Analyze events for all VMs, all VCPUs:
VM-EXIT Samples Samples% Time%
EPT_VIOLATION 9833984 63.41% 15.96%
IO_INSTRUCTION 2160843 13.93% 50.07%
EXTERNAL_INTERRUPT 1949267 12.57% 0.89%
APIC_WRITE 767795 4.95% 0.55%
EOI_INDUCED 615308 3.97% 0.30%
HLT 130821 0.84% 31.77%
after:
Analyze events for all VMs, all VCPUs:
VM-EXIT Samples Samples% Time%
EPT_VIOLATION 5238031 50.91% 6.44%
IO_INSTRUCTION 2257658 21.94% 54.88%
EXTERNAL_INTERRUPT 1160086 11.28% 0.61%
APIC_WRITE 780454 7.59% 0.54%
EOI_INDUCED 615309 5.98% 0.28%
HLT 179703 1.75% 36.87%
Signed-off-by: Evanzhang <evanzh...@archeros.com>
---
hw/rtc/mc146818rtc.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/hw/rtc/mc146818rtc.c b/hw/rtc/mc146818rtc.c
index c27c362..2995078 100644
--- a/hw/rtc/mc146818rtc.c
+++ b/hw/rtc/mc146818rtc.c
@@ -96,8 +96,8 @@ static void rtc_coalesced_timer_update(MC146818RtcState *s)
if (s->irq_coalesced == 0) {
timer_del(s->coalesced_timer);
} else {
- /* divide each RTC interval to 2 - 8 smaller intervals */
- int c = MIN(s->irq_coalesced, 7) + 1;
+ /* divide each RTC interval to 2 - 32 smaller intervals */
+ int c = MIN(s->irq_coalesced, 31) + 1;
int64_t next_clock = qemu_clock_get_ns(rtc_clock) +
periodic_clock_to_ns(s->period / c);
timer_mod(s->coalesced_timer, next_clock);
--
2.9.5
