Re: [PATCH v5 6/7] genirq: Adaptive Global Software Interrupt Moderation (GSIM).
| Newsgroups | org.kernel.vger.linux-pci |
|---|---|
| Message-ID | <[email protected]> |
> GSIM helps keeping system load (as defined later) under control, but > the use of a fixed moderation delay causes unnecessary latency when the > system load is already low. > > We focus on two types of system load related to interrupts: > - total device interrupt rates. Some platforms show severe I/O > performance degradation with more than 1-2 Mintr/s across the entire > system. This affects especially server-class hardware with hundreds of > interrupt sources (NIC or SSD queues from many physical or virtualized > devices). > - percentage of time spent in hardirq. This can become problematic in > presence of large numbers of interrupt sources hitting individual CPUs > (for instance, as a result of attempts to isolate application CPUs > from interrupt load). > > [ ... ] > hardirq_percent (delay_us = 200, target_intr_rate=0, iodepth 128) > hardirq% 1 10 20 30 40 50 60 70 > KIOPS 13900 13800 13300 12100 10400 8600 7400 6500 > > Signed-off-by: Luigi Rizzo <[email protected]> Sashiko has reviewed this patch and found no issues. It looks great! -- Sashiko AI review · https://sashiko.dev/#/patchset/[email protected]?part=6