openclaw - 💡(How to fix) Fix [Bug]: Gateway background work causes high CPU and page fault churn [1 pull requests]

Bug type

Behavior bug (incorrect output/state without crash)

Beta release blocker

No

Summary

Gateway background work can keep the process above one full CPU core with high minor page-fault churn even when diagnostic active/waiting/queued counters are zero.

Steps to reproduce

1. Run a gateway with memory-core dreaming and compaction/checkpoint sidecars enabled.
2. Observe the gateway process during background work when no foreground request is queued.
3. Capture CPU, memory, and liveness diagnostics for the gateway process.

Expected behavior

Background work should downshift or defer when gateway RSS, heap, CPU, or event-loop pressure is high so it does not keep the gateway above one core while no foreground work is queued.

Actual behavior

Observed samples showed the gateway using about 1.1-1.2 CPU cores while active/waiting/queued were zero. The same window showed high system CPU, high minor page-fault rates, private anonymous RSS over 2.6 GiB, and liveness warnings for CPU/event-loop pressure.

OpenClaw version

NOT_ENOUGH_INFO

Operating system

NOT_ENOUGH_INFO

Install method

NOT_ENOUGH_INFO

Model

NOT_ENOUGH_INFO

Provider / routing chain

NOT_ENOUGH_INFO

Additional provider/model setup details

NOT_ENOUGH_INFO

Logs, screenshots, and evidence

process sample: RSS=2745172 kB PSS=2691306 kB Private_Dirty=2674492 kB Anonymous=2674464 kB Swap=0 kB
pidstat 5s average: usr=74.80 system=42.00 cpu=116.80
pidstat memory 5s average: minflt/s=154878.64 majflt/s=0.00 rss=2234887 kB
memory pressure: level=warning reason=rss_threshold rssBytes=1827979264 heapUsedBytes=684072312 thresholdBytes=1610612736
liveness warning: reasons=event_loop_delay,event_loop_utilization,cpu eventLoopDelayP99Ms=306.2 eventLoopDelayMaxMs=1163.9 eventLoopUtilization=0.991 cpuCoreRatio=1.107 active=0 waiting=0 queued=0

Impact and severity

Affected: gateways with background memory/checkpoint work enabled. Severity: high for gateway responsiveness. Frequency: observed in two live pidstat samples from the same investigation. Consequence: background sidecars can consume CPU and memory budget that should remain available for chat latency, websocket control traffic, timers, and health checks.

Additional information

Primary fix path: bound and pressure-defer managed memory-core dreaming. Related fix path: cap retained compaction checkpoint bytes so old large checkpoint artifacts do not keep accumulating per session.