From usernkey at gmail.com Wed May 13 00:56:20 2015 From: usernkey at gmail.com (Marco Giovannini) Date: Wed, 13 May 2015 09:56:20 +0200 Subject: [Kernelfeatures-devel] high memory usage and hugepage setting Message-ID: Hi guys I'm using Oracle Linux Server release 6.4 with UEK kernel 2.6.39-400.209.1.el6uek.x86_64. I saw in config file of the kernel that UEK does not use trasparent huge page. # CONFIG_TRANSPARENT_HUGEPAGE is not set This is not a issue for me as I'm running Oracle RAC and I could not use it anyway :) My current setting kernel setting for RAC are provided using the oracle package 'oracle-rdbms-server-11gR2-preinstall-1.0-7.el6.x86_64' + some additional conf added manually net.ipv4.ip_forward = 0 net.ipv4.conf.default.rp_filter = 0 net.ipv4.conf.default.accept_source_route = 0 kernel.sysrq = 0 kernel.core_uses_pid = 1 net.ipv4.tcp_syncookies = 1 net.bridge.bridge-nf-call-ip6tables = 0 net.bridge.bridge-nf-call-iptables = 0 net.bridge.bridge-nf-call-arptables = 0 kernel.msgmnb = 65536 kernel.msgmax = 65536 fs.file-max = 6815744 kernel.sem = 250 32000 100 128 kernel.shmmni = 4096 kernel.shmall = 1073741824 kernel.shmmax = 4398046511104 net.core.rmem_default = 262144 net.core.rmem_max = 4194304 net.core.wmem_default = 262144 net.core.wmem_max = 1048576 fs.aio-max-nr = 1048576 net.ipv4.ip_local_port_range = 9000 65500 vm.swappiness=0 vm.max_map_count=524280 vm.min_free_kbytes=512000 vm.nr_hugepages=5389 I'm having an high usage of memory but I was not able to identify the processes/cache/buffer with high usage MemTotal: 16330600 kB MemFree: 936424 kB Buffers: 3996 kB Cached: 595708 kB SwapCached: 835748 kB Active: 1931588 kB Inactive: 1204540 kB Active(anon): 1717000 kB Inactive(anon): 993436 kB Active(file): 214588 kB Inactive(file): 211104 kB Unevictable: 325580 kB Mlocked: 325580 kB SwapTotal: 18870268 kB SwapFree: 17368004 kB Dirty: 1696 kB Writeback: 0 kB AnonPages: 2855972 kB Mapped: 221064 kB Shmem: 93984 kB Slab: 464292 kB SReclaimable: 51728 kB SUnreclaim: 412564 kB KernelStack: 6600 kB PageTables: 131396 kB NFS_Unstable: 0 kB Bounce: 0 kB WritebackTmp: 0 kB CommitLimit: 21517232 kB Committed_AS: 7045840 kB VmallocTotal: 34359738367 kB VmallocUsed: 359380 kB VmallocChunk: 34359321188 kB HardwareCorrupted: 0 kB HugePages_Total: 5389 HugePages_Free: 1086 HugePages_Rsvd: 1076 HugePages_Surp: 0 Hugepagesize: 2048 kB DirectMap4k: 10240 kB DirectMap2M: 16766976 kB I was wondering if could be relate to the hugepage settings. 5389 x 2M = ~11G on a system with 15G of ram Is all the space (in my case 11G) reserved at boot time or it is reserved based on the need ? Regards, Marco -------------- next part -------------- An HTML attachment was scrubbed... URL: http://oss.oracle.com/pipermail/kernelfeatures-devel/attachments/20150513/109b3e7b/attachment.html