On 2014-02-23 20:04:39 +0100, Pavel Stehule wrote: > 354246.00 93.0% s_lock > /usr/lib/postgresql/9.2/bin/postgres > 10503.00 2.8% LWLockRelease > /usr/lib/postgresql/9.2/bin/postgres > 8802.00 2.3% LWLockAcquire > /usr/lib/postgresql/9.2/bin/postgres > 828.00 0.2% _raw_spin_lock > [kernel.kallsyms] > 559.00 0.1% _raw_spin_lock_irqsave > [kernel.kallsyms] > 340.00 0.1% switch_mm > [kernel.kallsyms] > 305.00 0.1% poll_schedule_timeout > [kernel.kallsyms] > 274.00 0.1% native_write_msr_safe > [kernel.kallsyms] > 257.00 0.1% _raw_spin_lock_irq > [kernel.kallsyms] > 238.00 0.1% apic_timer_interrupt > [kernel.kallsyms] > 236.00 0.1% __schedule > [kernel.kallsyms] > 213.00 0.1% HeapTupleSatisfiesMVCC > > With systemtap I got list of spin locks > > light weight locks > lockname mode count avg (time) > DynamicLocks Exclusive 2804 1025 > DynamicLocks Shared 106 130 > ProcArrayLock Exclusive 63 963551 > ProcArrayLock Shared 50 4160 > LockMgrLocks Exclusive 18 159 > IndividualLock Exclusive 2 7 > > There is relative few very long ProcArrayLocks lwlocks
It's odd that there are so many exclusive acquisition ProcArrayLocks... A hierarchical profile would be interesting. I'd suggest compiling postgres with -fno-omit-frame-pointer and doing a profile with perf. Greetings, Andres Freund -- Andres Freund http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Training & Services -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
