topic Re: High Memory utilization in Operating System - Linux https://community.hpe.com/t5/operating-system-linux/high-memory-utilization/m-p/5635221#M53652 <P>Low/reserved ram and additional pages are reserved by the kernel, not displayed in "free" and not typically 4gigs. &nbsp; I see Oracle is running here, did the oracle installer expand ulimits, increase kernel table sizes perhaps? &nbsp;I don't know if you have identical hardware handy, but it'd be interesting to see the memory totals with an untweaked kernel (one that possibly doesn't consume 4gigs).</P><P>&nbsp;</P><P>curiously,</P><P>-craig</P><P>&nbsp;</P> Wed, 25 Apr 2012 17:12:18 GMT craiger_ 2012-04-25T17:12:18Z High Memory utilization https://community.hpe.com/t5/operating-system-linux/high-memory-utilization/m-p/5634503#M53651 <P>Redhat Linux version : 5.6</P><P>&nbsp;</P><P>[root@sl]# free<BR />&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; total&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; used&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; free&nbsp;&nbsp;&nbsp;&nbsp; shared&nbsp;&nbsp;&nbsp; buffers&nbsp;&nbsp;&nbsp;&nbsp; cached<BR />Mem:&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 16436192&nbsp;&nbsp; 16313340&nbsp;&nbsp;&nbsp;&nbsp; 122852&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 0&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 16752&nbsp;&nbsp;&nbsp; 1674012<BR />-/+ buffers/cache:&nbsp;&nbsp; 14622576&nbsp;&nbsp;&nbsp; 1813616<BR />Swap:&nbsp;&nbsp;&nbsp;&nbsp; 18874360&nbsp;&nbsp;&nbsp; 2769164&nbsp;&nbsp; 16105196</P><P>&nbsp;</P><P>&nbsp;</P><P>[root@sl]# more /proc/meminfo<BR />MemTotal:&nbsp;&nbsp;&nbsp;&nbsp; 16436192 kB<BR />MemFree:&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 122604 kB<BR />Buffers:&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 17112 kB<BR />Cached:&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 1674340 kB<BR />SwapCached:&nbsp;&nbsp;&nbsp;&nbsp; 353740 kB<BR />Active:&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 3332188 kB<BR />Inactive:&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 48784 kB<BR />HighTotal:&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 0 kB<BR />HighFree:&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 0 kB<BR />LowTotal:&nbsp;&nbsp;&nbsp;&nbsp; 16436192 kB<BR />LowFree:&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 122604 kB<BR />SwapTotal:&nbsp;&nbsp;&nbsp; 18874360 kB<BR />SwapFree:&nbsp;&nbsp;&nbsp;&nbsp; 16105196 kB<BR />Dirty:&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 968 kB<BR />Writeback:&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 0 kB<BR />AnonPages:&nbsp;&nbsp;&nbsp;&nbsp; 1685236 kB<BR />Mapped:&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 1585500 kB<BR />Slab:&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 72584 kB<BR />PageTables:&nbsp;&nbsp;&nbsp;&nbsp; 180108 kB<BR />NFS_Unstable:&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 0 kB<BR />Bounce:&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 0 kB<BR />CommitLimit:&nbsp; 20801000 kB<BR />Committed_AS:&nbsp; 8598100 kB<BR />VmallocTotal: 34359738367 kB<BR />VmallocUsed:&nbsp;&nbsp;&nbsp; 316556 kB<BR />VmallocChunk: 34359421495 kB<BR />HugePages_Total:&nbsp; 6144<BR />HugePages_Free:&nbsp;&nbsp; 5318<BR />HugePages_Rsvd:&nbsp;&nbsp;&nbsp; 440<BR />Hugepagesize:&nbsp;&nbsp;&nbsp;&nbsp; 2048 kB<BR /><BR /></P><P>&nbsp;</P><P>&nbsp;</P><P>top - 03:05:45 up 95 days, 11:29,&nbsp; 3 users,&nbsp; load average: 1.92, 1.76, 1.72<BR />Tasks: 320 total,&nbsp;&nbsp; 1 running, 318 sleeping,&nbsp;&nbsp; 0 stopped,&nbsp;&nbsp; 1 zombie<BR />Cpu(s):&nbsp; 5.3%us,&nbsp; 2.4%sy,&nbsp; 0.0%ni, 47.4%id, 44.9%wa,&nbsp; 0.0%hi,&nbsp; 0.0%si,&nbsp; 0.0%st<BR />Mem:&nbsp; 16436192k total, 16317376k used,&nbsp;&nbsp; 118816k free,&nbsp;&nbsp;&nbsp; 17316k buffers<BR />Swap: 18874360k total,&nbsp; 2769164k used, 16105196k free,&nbsp; 1674636k cached<BR /><BR />&nbsp; PID USER&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; PR&nbsp; NI&nbsp; VIRT&nbsp; RES&nbsp; SHR S %CPU %MEM&nbsp;&nbsp;&nbsp; TIME+&nbsp; COMMAND<BR />30984 oracle&nbsp;&nbsp;&nbsp; 15&nbsp;&nbsp; 0 2791m 1.3g 1.3g S&nbsp; 0.8&nbsp; 8.3&nbsp; 49:51.66 oracle<BR />19241 oracle&nbsp;&nbsp;&nbsp; 15&nbsp;&nbsp; 0 2470m 1.1g&nbsp; 11m S&nbsp; 0.8&nbsp; 6.9 679:08.51 oraagent.bin<BR />&nbsp;7890 oracle&nbsp;&nbsp;&nbsp; 15&nbsp;&nbsp; 0 2757m 670m 670m S&nbsp; 0.0&nbsp; 4.2&nbsp;&nbsp; 0:01.68 oracle<BR />&nbsp;5415 oracle&nbsp;&nbsp;&nbsp; 15&nbsp;&nbsp; 0 2765m 393m 388m S&nbsp; 0.0&nbsp; 2.5&nbsp;&nbsp; 0:05.98 oracle<BR />&nbsp;7894 oracle&nbsp;&nbsp;&nbsp; 15&nbsp;&nbsp; 0 2781m 374m 373m S&nbsp; 0.0&nbsp; 2.3&nbsp;&nbsp; 0:03.79 oracle<BR />&nbsp;5418 oracle&nbsp;&nbsp;&nbsp; 15&nbsp;&nbsp; 0 2767m 370m 365m S&nbsp; 0.0&nbsp; 2.3&nbsp;&nbsp; 0:05.88 oracle<BR />28110 oracle&nbsp;&nbsp;&nbsp; 15&nbsp;&nbsp; 0 2765m 359m 357m S&nbsp; 0.0&nbsp; 2.2&nbsp;&nbsp; 0:13.80 oracle<BR />&nbsp;7898 oracle&nbsp;&nbsp;&nbsp; 15&nbsp;&nbsp; 0 2768m 348m 347m S&nbsp; 0.0&nbsp; 2.2&nbsp;&nbsp; 0:03.88 oracle<BR />&nbsp;7910 oracle&nbsp;&nbsp;&nbsp; 15&nbsp;&nbsp; 0 2765m 317m 313m S&nbsp; 0.0&nbsp; 2.0&nbsp;&nbsp; 0:11.49 oracle<BR />&nbsp;7166 oracle&nbsp;&nbsp;&nbsp; 15&nbsp;&nbsp; 0 2767m 217m 212m S&nbsp; 0.0&nbsp; 1.4&nbsp;&nbsp; 0:01.93 oracle<BR />12021 oracle&nbsp;&nbsp;&nbsp; 15&nbsp;&nbsp; 0 2769m 213m 201m S&nbsp; 0.0&nbsp; 1.3&nbsp;&nbsp; 0:01.80 oracle<BR />14811 oracle&nbsp;&nbsp;&nbsp; 15&nbsp;&nbsp; 0 2764m 207m 205m S&nbsp; 0.0&nbsp; 1.3&nbsp;&nbsp; 0:02.70 oracle<BR />&nbsp;7464 oracle&nbsp;&nbsp;&nbsp; 15&nbsp;&nbsp; 0 2762m 179m 179m S&nbsp; 0.0&nbsp; 1.1&nbsp;&nbsp; 0:55.95 oracle<BR />28180 oracle&nbsp;&nbsp;&nbsp; 15&nbsp;&nbsp; 0 2762m 165m 163m S&nbsp; 0.0&nbsp; 1.0&nbsp;&nbsp; 0:28.38 oracle<BR />&nbsp;7926 oracle&nbsp;&nbsp;&nbsp; 15&nbsp;&nbsp; 0 2765m 160m 157m S&nbsp; 0.0&nbsp; 1.0&nbsp;&nbsp; 0:24.77 oracle<BR />&nbsp;7147 oracle&nbsp;&nbsp;&nbsp; 15&nbsp;&nbsp; 0 2762m 145m 141m S&nbsp; 0.0&nbsp; 0.9&nbsp;&nbsp; 0:10.35 oracle<BR />28199 oracle&nbsp;&nbsp;&nbsp; 15&nbsp;&nbsp; 0 2762m 139m 136m S&nbsp; 0.0&nbsp; 0.9&nbsp;&nbsp; 0:15.57 oracle<BR />28152 oracle&nbsp;&nbsp;&nbsp; 15&nbsp;&nbsp; 0 2762m 136m 133m S&nbsp; 0.0&nbsp; 0.8&nbsp;&nbsp; 0:13.16 oracle<BR />19899 oracle&nbsp;&nbsp;&nbsp; 15&nbsp;&nbsp; 0 2763m 133m 133m S&nbsp; 0.0&nbsp; 0.8&nbsp;&nbsp; 0:01.98 oracle<BR />&nbsp;7263 oracle&nbsp;&nbsp;&nbsp; 15&nbsp;&nbsp; 0 2762m 118m 115m S&nbsp; 0.0&nbsp; 0.7&nbsp;&nbsp; 0:06.00 oracle<BR />24326 oracle&nbsp;&nbsp;&nbsp; 15&nbsp;&nbsp; 0 2764m 109m 105m S&nbsp; 0.0&nbsp; 0.7&nbsp;&nbsp; 0:01.41 oracle<BR />&nbsp;5924 oracle&nbsp;&nbsp;&nbsp; 15&nbsp;&nbsp; 0 2767m 108m 102m S&nbsp; 0.0&nbsp; 0.7&nbsp;&nbsp; 0:00.76 oracle<BR />11042 oracle&nbsp;&nbsp;&nbsp; 15&nbsp;&nbsp; 0 2762m 107m 105m S&nbsp; 0.0&nbsp; 0.7&nbsp;&nbsp; 0:07.57 oracle<BR />&nbsp;3567 oracle&nbsp;&nbsp;&nbsp; 15&nbsp;&nbsp; 0 2761m 107m 105m S&nbsp; 0.0&nbsp; 0.7&nbsp;&nbsp; 0:00.69 oracle<BR />28144 oracle&nbsp;&nbsp;&nbsp; 15&nbsp;&nbsp; 0 2762m 100m&nbsp; 97m S&nbsp; 0.0&nbsp; 0.6&nbsp;&nbsp; 0:00.54 oracle<BR />&nbsp;7218 oracle&nbsp;&nbsp;&nbsp; 15&nbsp;&nbsp; 0 2762m&nbsp; 94m&nbsp; 92m S&nbsp; 0.0&nbsp; 0.6&nbsp;&nbsp; 0:00.27 oracle</P><P>&nbsp;</P><P>&nbsp;</P><P>Question:-&nbsp; The free buffer/cache size in free commands shows 1813616K. Whereas if i do ps aux command to find out total amount of memory used by all the processes then it comes to around 10GB(see attachment). So as per ps aux command it tells me that i should have 4gb free out of total physical 16gb but the free buffer/cache is only 1.8G free. what else could be eating up the memory.</P> Wed, 25 Apr 2012 07:11:13 GMT https://community.hpe.com/t5/operating-system-linux/high-memory-utilization/m-p/5634503#M53651 sbahra 2012-04-25T07:11:13Z Re: High Memory utilization https://community.hpe.com/t5/operating-system-linux/high-memory-utilization/m-p/5635221#M53652 <P>Low/reserved ram and additional pages are reserved by the kernel, not displayed in "free" and not typically 4gigs. &nbsp; I see Oracle is running here, did the oracle installer expand ulimits, increase kernel table sizes perhaps? &nbsp;I don't know if you have identical hardware handy, but it'd be interesting to see the memory totals with an untweaked kernel (one that possibly doesn't consume 4gigs).</P><P>&nbsp;</P><P>curiously,</P><P>-craig</P><P>&nbsp;</P> Wed, 25 Apr 2012 17:12:18 GMT https://community.hpe.com/t5/operating-system-linux/high-memory-utilization/m-p/5635221#M53652 craiger_ 2012-04-25T17:12:18Z