Topic: Approaching the limit on PV entries
After experiencing elevated traffic one day, both my database and web server hsd the following in the messages file:
Sep 21 11:22:49 dbase kernel: Approaching the limit on PV entries, consider increasing either the vm.pmap.shpgperproc or the vm.pmap.pv_entry_max sysctl.
The following was already set:
kern.ipc.shm_use_phys=1
---------
# sysctl vm.pmap
vm.pmap.pmap_collect_active: 0
vm.pmap.pmap_collect_inactive: 0
vm.pmap.pv_entry_spare: 6811
vm.pmap.pv_entry_allocs: 240355755838
vm.pmap.pv_entry_frees: 240355712585
vm.pmap.pc_chunk_tryfail: 0
vm.pmap.pc_chunk_frees: 1365293597
vm.pmap.pc_chunk_allocs: 1365293895
vm.pmap.pc_chunk_count: 298
vm.pmap.pv_entry_count: 43253
vm.pmap.shpgperproc: 200
vm.pmap.pv_entry_max: 2653183
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FreeBSD 7.1-PRERELEASE #1: Mon Dec 1 14:17:24 EST 2008
cdizz@dbasenet:/usr/obj/usr/src/sys/PRO180
Timecounter "i8254" frequency 1193182 Hz quality 0
CPU: Intel(R) Xeon(R) CPU E5420 @ 2.50GHz (2503.74-MHz K8-class CPU)
Origin = "GenuineIntel" Id = 0x1067a Stepping = 10
Features=0xbfebfbff<FPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,PGE,MCA,CMOV,PAT,PSE36,CLFLUSH,DTS,ACPI,MMX,FXSR,SSE,SSE2,SS,HTT,TM,PBE>
Features2=0x40ce3bd<SSE3,RSVD2,MON,DS_CPL,VMX,EST,TM2,SSSE3,CX16,xTPR,PDCM,DCA,<b19>,<b26>>
AMD Features=0x20100800<SYSCALL,NX,LM>
AMD Features2=0x1<LAHF>
Cores per package: 4
usable memory = 4282134528 (4083 MB)
avail memory = 4126793728 (3935 MB)