Reduce Futex Spinlock CPU Usage

I’m running an Centos ngix issue with futex-related spinlocks (futex_wait_queue_me, futex_wake, _raw_spin_lock, etc.). Even indirect users such as malloc/free, rand(), and glib-level pthread mutexes trigger the same hotspots.

My sole objective is reduced CPU usage; raw throughput is acceptable, but wasted spin time is not. I need an expert who can analyse and mitigate this contention, whether that means kernel patching, glibc tweaks, alternative allocators (jemalloc, tcmalloc), Nginx worker affinity, or any other proven technique that eliminates the excessive spinning.

Scope of work
• Profile and confirm the exact futex bottlenecks on my setup (I can supply live traffic traces or synthetic workloads).
• Propose and implement changes—kernel, userspace, or configuration—that cut the spin-lock share of CPU.
• Validate the improvement with before/after metrics (perf top/record, vmstat, or your preferred tool).

Acceptance criteria
• At least 50 % drop in CPU samples attributed to futex spinlocks during identical load.
• No regression in request latency or error rate.
• Clear documentation of every change so I can reproduce the build on staging and production.

SSH access to a staging clone is available, and I can reboot or recompile kernels as needed. If you’ve tamed futex contention on high-traffic Nginx systems before, I’d love to see how you’d tackle mine.