您还可以使用以下方式登录
当前位置：&>&&>&&>& > 【翻译自mos文章】在使用Linux大页内存的配置中，使用drop_cache时导致的ORA-600[KGHLKREM1]问题
【翻译自mos文章】在使用Linux大页内存的配置中，使用drop_cache时导致的ORA-600[KGHLKREM1]问题
在使用Linux大页内存的配置中，使用drop_cache时导致的ORA-600 [KGHLKREM1]问题来源于：ORA-600 [KGHLKREM1] On Linux Using Parameter drop_cache On hugepages Configuration (文档 ID )适用于：Oracle Database - Enterprise Edition - Version 10.2.0.1 and laterGeneric Linux***Checked for relevance on 29-Jul-2013***症状：你正在运行一个Oracle database，单实例数据库或者rac。你使用基于大页内存的sga你遇到下面的问题：ORA-00600: internal error code, arguments: [KGHLKREM1], [0x06BC00020]with stack trace similar to: kghnerror kghadd_reserved_ext kghgex-- or alsoORA-07445: exception encountered: core dump[kglhdal()+1105][SIGSEGV] [Address not mapped to object] [0x] [] []ORA-07445: exception encountered: core dump [kghfnd()+2328] [SIGSEGV][Address not mapped to object] [0xFFFFFFFFFFFFFFF0] [] []对侵犯地址（在上面的例子中是0x6bc00020）进行SGA heap dump显示，被清零（zeroed out）asm1_lmd0_8600.trc~~~~~~~~~~~~~~~~~~***
15:57:38.274***** Internal heap ERROR KGHLKREM1 addr=0x6c400020 ds=0x ********** Dump of memory around addr 0x6cC3FF020 00
[................]Repeat 511 times&变化：1.在你的系统中，你正在运行vm.drop_caches=1 (or 3)，drop_cache被设置为一个非零值，或者你在执行：echo 3 & /proc/sys/vm/drop_caches如下关于drop_caches的解释，不做翻译，原文如下：/proc/sys/vm/drop_caches (since Linux 2.6.16)Writing to this file causes the kernel to drop clean caches, dentries and inodes from memory, causing that memory to become free.To free pagecache:* echo 1 & /proc/sys/vm/drop_cachesTo free dentries and inodes:* echo 2 & /proc/sys/vm/drop_cachesTo free pagecache, dentries and inodes:* echo 3 & /proc/sys/vm/drop_cachesAs this is a non-destructive operation, and dirty objects are not freeable, the user should run &sync& first in order to make sure all cached objects are freed.2.已经使用Linux的大页内存。原因：这是Linux 内核的问题使用Linux内核drop_cache参数和大页内存时，内存损坏会发生。Per internal Bug 9461825, executing vm.drop_caches corrupts Oracle Database SGA hugepages.This is fixed in Linux Kernel version 2.6.18-194.0.0.0.4.EL5解决方案：1.
As a workaround when hugepages are set avoid any vm.drop_cache settings.- OR -2.
Upgrade to Linux Kernel version 2.6.18-194.0.0.0.4.EL5参考：BUG:9358381 - ASM INSTANCE IS CRASHING AS ORA-600[KGHLKREM1] WHEN HUGEPAGES ARE IN USE就爱阅读网友整理上传,为您提供最全的知识大全,期待您的分享，转载请注明出处。
欢迎转载：
推荐： 　　　Linux 关于Transparent Hugepages的介绍 - 王朝网络 -
分享&&&&&当前位置: &&&&&&&&Linux 关于Transparent Hugepages的介绍&&&　　linux 关于Transparent Hugepages的介绍
16:54 by 潇湘隐者, ... 阅读, ... 评论, 收藏,
透明大页介绍 Transparent Huge Pages的一些官方介绍资料： Transparent Huge Pages (THP) are enabled by default in RHEL 6 for all applications. The kernel attempts to allocate hugepages whenever possible and any Linux PRocess will receive 2MB pages if the mmap region is 2MB naturally aligned. The main kernel address space itself is mapped with hugepages, reducing TLB pressure from kernel code. For general information on Hugepages, see: What are Huge Pages and what are the advantages of using them? The kernel will always attempt to satisfy a memory allocation using hugepages. If no hugepages are available (due to non availability of physically continuous memory for example) the kernel will fall back to the regular 4KB pages. THP are also swappable (unlike hugetlbfs). This is achieved by breaking the huge page to smaller 4KB pages, which are then swapped out normally. But to use hugepages effectively, the kernel must find physically continuous areas of memory big enough to satisfy the request, and also properly aligned. For this, a khugepaged kernel thread has been added. This thread will occasionally attempt to substitute smaller pages being used currently with a hugepage allocation, thus maximizing THP usage. In userland, no modifications to the applications are necessary (hence transparent). But there are ways to optimize its use. For applications that want to use hugepages, use of posix_memalign() can also help ensure that large allocations are aligned to huge page (2MB) boundaries. Also, THP is only enabled for anonymous memory regions. There are plans to add support for tmpfs and page cache. THP tunables are found in the /sys tree under /sys/kernel/mm/redhat_transparent_hugepage.
查看是否启用透明大页 1：命令cat /sys/kernel/mm/redhat_transparent_hugepage/enabled 该命令适用于Red Hat Enterprise Linux系统　　 [root@getlnx06 ~]# more /etc/issue　　Red Hat Enterprise Linux Server release 6.6 (Santiago)　　Kernel \r on an \m　　[root@getlnx06 ~]# cat /sys/kernel/mm/redhat_transparent_hugepage/enabled　　[always] madvise never　　2：命令cat /sys/kernel/mm/transparent_hugepage/enabled 该命令适用于其它Linux系统　　[root@getlnx06 ~]# cat /sys/kernel/mm/transparent_hugepage/enabled　　always madvise [never]　　[root@getlnx06 ~]# 　　使用命令查看时，如果输出结果为[always]表示透明大页启用了。[never]表示透明大页禁用、[madvise]表示 3：如何HugePages_Total返回0，也意味着透明大页禁用了　　[root@getlnx06 ~]# grep -i HugePages_Total /proc/meminfo 　　HugePages_Total: 0　　4：cat /proc/sys/vm/nr_hugepages返回0也意味着透明大页禁用了。　　[root@getlnx06 ~]# cat /proc/sys/vm/nr_hugepages 　　0　　禁用、启用透明大页功能 方法1：设置/etc/grub.conf文件，在系统启动是禁用。　　[root@getlnx06 ~]# vi /etc/grub.conf　　# grub.conf generated by anaconda　　#　　# Note that you do not have to rerun grub after making changes to this file　　# NOTICE: You have a /boot partition. This means that　　# all kernel and initrd paths are relative to /boot/, eg.　　# root (hd0,0)　　# kernel /vmlinuz-version ro root=/dev/mapper/VolGroup--LogVol0-LogVol01　　# initrd /initrd-[generic-]version.img　　#boot=/dev/sda　　default=0　　timeout=5　　splashimage=(hd0,0)/grub/splash.xpm.gz　　hiddenmenu　　title Red Hat Enterprise Linux 6 (2.6.32-504.el6.x86_64)　　root (hd0,0)　　kernel /vmlinuz-2.6.32-504.el6.x86_64 ro root=/dev/mapper/VolGroup--LogVol0-LogVol01 rd_NO_LUKS LANG=en_US.UTF-8 rd_NO_MD SYSFONT=latarcyrheb-sun16 crashkernel=auto rd_LVM_LV=VolGroup-LogVol0/LogVol01 rd_LVM_LV=VolGroup-LogVol0/LogVol00 KEYBOARDTYPE=pc KEYTABLE=us rd_NO_DM rhgb quiet　　initrd /initramfs-2.6.32-504.el6.x86_64.img　　transparent_hugepage=never　　方法2：设置/etc/rc.local文件　　[root@getlnx06 ~]# vi /etc/rc.local　　#!/bin/sh　　#　　# This script will be executed *after* all the other init scripts.　　# You can put your own initialization stuff in here if you don't　　# want to do the full Sys V style init stuff.　　touch /var/lock/subsys/local　　if test -f /sys/kernel/mm/redhat_transparent_hugepage/ then　　echo never & /sys/kernel/mm/redhat_transparent_hugepage/enabled　　fi　　使用上面的配置后必须重启操作系统才能生效，你也可以运行下面命令不用重启操作系统。You must reboot your system for the setting to take effect, or run the following two echo lines to proceed with the install without rebooting:　　[root@getlnx06 ~]# echo never & /sys/kernel/mm/redhat_transparent_hugepage/enabled　　[root@getlnx06 ~]# cat /sys/kernel/mm/redhat_transparent_hugepage/enabled　　always madvise [never]　　[root@getlnx06 ~]# 　　小知识点：1：从RedHat 6, OEL 6, SLES 11 and UEK2 kernels 开始，系统缺省会启用 Transparent HugePages ：用来提高内存管理的性能透明大页（Transparent HugePages ）和之前版本中的大页功能上类似。主要的区别是：Transparent HugePages 可以实时配置，不需要重启才能生效配置； 2：Transparent Huge Pages在32位的RHEL 6中是不支持的。Transparent Huge Pages are not available on the 32-bit version of RHEL 6. 3： Oracle官方不建议我们使用RedHat 6, OEL 6, SLES 11 and UEK2 kernels 时的开启透明大页（Transparent HugePages ）， 因为透明大页（Transparent HugePages ） 存在一些问题： 1.在RAC环境下 透明大页（Transparent HugePages ）会导致异常节点重启，和性能问题； 2.在单机环境中，透明大页（Transparent HugePages ） 也会导致一些异常的性能问题；Transparent HugePages memory is enabled by default with Red Hat Enterprise Linux 6, SUSE Linux Enterprise Server 11, and Oracle Linux 6 with earlier releases of Oracle Linux Unbreakable Enterprise Kernel 2 (UEK2) kernels. Transparent HugePages memory is disabled in later releases of Oracle Linux UEK2 kernels.Transparent HugePages can cause memory allocation delays during runtime. To avoid performance issues, Oracle recommends that you disable Transparent HugePages on all Oracle Database servers. Oracle recommends that you instead use standard HugePages for enhanced performance.Transparent HugePages memory differs from standard HugePages memory because the kernel khugepaged thread allocates memory dynamically during runtime. Standard HugePages memory is pre-allocated at startup, and does not change during runtime.Starting with RedHat 6, OEL 6, SLES 11 and UEK2 kernels, Transparent HugePages are implemented and enabled (default) in an attempt to improve the memory management. Transparent HugePages are similar to the HugePages that have been available in previous Linux releases. The main difference is that the Transparent HugePages are set up dynamically at run time by the khugepaged thread in kernel while the regular HugePages had to be preallocated at the boot up time. Because Transparent HugePages are known to cause unexpected node reboots and performance problems with RAC, Oracle strongly advises to disable the use of Transparent HugePages. In addition, Transparent Hugepages may cause problems even in a single-instance database environment with unexpected performance problems or delays. As such, Oracle recommends disabling Transparent HugePages on all Database servers running Oracle. 4：安装Vertica Analytic Database时也必须关闭透明大页功能。 参考资料：/solutions/46111http://www.soso.io/article/65143.html&&&&&今日推荐
&&&&&日版宠物情人2017的插曲，很带节奏感，日语的，女生唱的。
最后听见是在第8集的时候女主手割伤了，然后男主用嘴帮她吸了一下，插曲就出来了。
歌手：Def...老钟家的两个儿子很特别，就是跟其他的人不太一样，魔一般的执着。兄弟俩都到了要结婚的年龄了，不管自家老爹怎么磨破嘴皮子，兄弟俩说不娶就不娶，老父母为兄弟两操碎了心...把牛仔裤磨出有线的破洞
1、具体工具就是磨脚石，下面垫一个硬物，然后用磨脚石一直磨一直磨，到把那块磨薄了，用手撕开就好了。出来的洞啊很自然的。需要猫须的话调几...先来看下敬业福和爱国福
今年春节，支付宝再次推出了“五福红包”活动，表示要“把欠大家的敬业福都还给大家”。
今天该活动正式启动，和去年一样，需要收集“五福”...有时候我们打开冰箱就会闻到一股异味，冰箱里的这种异味是因为一些物质发出的气味的混合体，闻起来让人恶心。 产生这些异味的主要原因有以下几点。
1、很多人有这种习...简介
《极品家丁》讲述了现代白领林晚荣无意回到古代金陵，并追随萧二小姐化名“林三”进入萧府，不料却阴差阳错上演了一出低级家丁拼搏上位的“林三升职记”。...你就是我最爱的宝宝 - 李溪芮
(电视剧《极品家丁》片尾曲)
作词：常馨内
作曲：常馨内
你的眉 又鬼马的挑
你的嘴 又坏坏的笑
上一秒吵闹 下...乌梅，又称春梅，中医认为，乌梅味酸，性温，无毒，具有安心、除热、下气、祛痰、止渴调中、杀虫的功效，治肢体痛、肺痨病。乌梅泡水喝能治伤寒烦热、止吐泻，与干姜一起制...什么是脂肪粒
在我们的脸上总会长一个个像脂肪的小颗粒，弄也弄不掉，而且颜色还是白白的。它既不是粉刺也不是其他的任何痘痘，它就是脂肪粒。
脂肪粒虽然也是由油脂...来源：中国青年报
新的攻击方法不断涌现，黑客几乎永远占据网络攻击的上风，我们不可能通过技术手段杜绝网络攻击。国家安全保障的主要方向是打击犯罪，而不是处置和惩罚...夫妻网络直播“造人”爆红
　　1月9日，温岭城北派出所接到南京警方的协查通告，他们近期打掉了一个涉黄直播APP平台。而根据掌握的线索，其中有一对涉案的夫妻主播...如何防止墙纸老化？
（1）选择透气性好的墙纸
市场上墙纸的材质分无纺布的、木纤维的、PVC的、玻璃纤维基材的、布面的等，相对而言，PVC材质的墙纸最不透气...观点一：破日本销售量的“鲜肌之谜” 非日本生产
近一段时间，淘宝上架了一款名为“鲜肌之谜的” 鲑鱼卵巢美容液，号称是最近日本的一款推出的全新护肤品，产品本身所...系腰裙(北宋词人 张先)
惜霜蟾照夜云天，朦胧影、画勾阑。人情纵似长情月，算一年年。又能得、几番圆。
欲寄西江题叶字，流不到、五亭前。东池始有荷新绿，尚小如...关于女人的经典语句1、【做一个独立的女人】
思想独立：有主见、有自己的人生观、价值观。有上进心,永远不放弃自己的理想，做一份自己喜爱的事业，拥有快乐和成就...你想体验机器人性爱吗？你想和性爱机器人结婚吗？如果你想，机器人有拒绝你的权利吗？
近日，第二届“国际人类-机器人性爱研讨会”大会在伦敦金史密斯大学落下帷幕。而...10.土耳其地下洞穴城市
变态指数：★★☆☆☆
这是土耳其卡帕多西亚的一个著名景点，传说是当年基督教徒们为了躲避战争而在此修建。里面曾住着20000人，......据英国《每日快报》报道，一位科学家兼理论家Robert Lanza博士宣称，世界上并不存在人类死亡，死亡的只是身体。他认为我们的意识借助我们体内的能量生存，而且...《我爱狐狸精》 - 刘馨棋
　　(电视剧《屏里狐》主题曲)
　　作词：金十三&李旦
　　作曲：刘嘉
　　狐狸精 狐狸仙
　　千年修...·&·&·&&&&&&linux 关于Transparent Hugepages的介绍
16:54 by 潇湘隐者, ... 阅读, ... 评论, 收藏,
透明大页介绍 Transparent Huge Pages的一些官方介绍资料： Transparent Huge Pages (THP) are enabled by default in RHEL 6 for all applications. The kernel attempts to allocate hugepages whenever possible and any Linux PRocess will receive 2MB pages if the mmap region is 2MB naturally aligned. The main kernel address space itself is mapped with hugepages, reducing TLB pressure from kernel code. For general information on Hugepages, see: What are Huge Pages and what are the advantages of using them? The kernel will always attempt to satisfy a memory allocation using hugepages. If no hugepages are available (due to non availability of physically continuous memory for example) the kernel will fall back to the regular 4KB pages. THP are also swappable (unlike hugetlbfs). This is achieved by breaking the huge page to smaller 4KB pages, which are then swapped out normally. But to use hugepages effectively, the kernel must find physically continuous areas of memory big enough to satisfy the request, and also properly aligned. For this, a khugepaged kernel thread has been added. This thread will occasionally attempt to substitute smaller pages being used currently with a hugepage allocation, thus maximizing THP usage. In userland, no modifications to the applications are necessary (hence transparent). But there are ways to optimize its use. For applications that want to use hugepages, use of posix_memalign() can also help ensure that large allocations are aligned to huge page (2MB) boundaries. Also, THP is only enabled for anonymous memory regions. There are plans to add support for tmpfs and page cache. THP tunables are found in the /sys tree under /sys/kernel/mm/redhat_transparent_hugepage.
查看是否启用透明大页 1：命令cat /sys/kernel/mm/redhat_transparent_hugepage/enabled 该命令适用于Red Hat Enterprise Linux系统
[root@getlnx06 ~]# more /etc/issue
Red Hat Enterprise Linux Server release 6.6 (Santiago)
Kernel \r on an \m
[root@getlnx06 ~]# cat /sys/kernel/mm/redhat_transparent_hugepage/enabled
[always] madvise never
2：命令cat /sys/kernel/mm/transparent_hugepage/enabled 该命令适用于其它Linux系统
[root@getlnx06 ~]# cat /sys/kernel/mm/transparent_hugepage/enabled
always madvise [never]
[root@getlnx06 ~]#
使用命令查看时，如果输出结果为[always]表示透明大页启用了。[never]表示透明大页禁用、[madvise]表示 3：如何HugePages_Total返回0，也意味着透明大页禁用了
[root@getlnx06 ~]# grep -i HugePages_Total /proc/meminfo
HugePages_Total: 0
4：cat /proc/sys/vm/nr_hugepages返回0也意味着透明大页禁用了。
[root@getlnx06 ~]# cat /proc/sys/vm/nr_hugepages
禁用、启用透明大页功能 方法1：设置/etc/grub.conf文件，在系统启动是禁用。
[root@getlnx06 ~]# vi /etc/grub.conf
# grub.conf generated by anaconda
# Note that you do not have to rerun grub after making changes to this file
# NOTICE: You have a /boot partition. This means that
# all kernel and initrd paths are relative to /boot/, eg.
# root (hd0,0)
# kernel /vmlinuz-version ro root=/dev/mapper/VolGroup--LogVol0-LogVol01
# initrd /initrd-[generic-]version.img
#boot=/dev/sda
splashimage=(hd0,0)/grub/splash.xpm.gz
hiddenmenu
title Red Hat Enterprise Linux 6 (2.6.32-504.el6.x86_64)
root (hd0,0)
kernel /vmlinuz-2.6.32-504.el6.x86_64 ro root=/dev/mapper/VolGroup--LogVol0-LogVol01 rd_NO_LUKS LANG=en_US.UTF-8 rd_NO_MD SYSFONT=latarcyrheb-sun16 crashkernel=auto rd_LVM_LV=VolGroup-LogVol0/LogVol01 rd_LVM_LV=VolGroup-LogVol0/LogVol00 KEYBOARDTYPE=pc KEYTABLE=us rd_NO_DM rhgb quiet
initrd /initramfs-2.6.32-504.el6.x86_64.img
transparent_hugepage=never
方法2：设置/etc/rc.local文件
[root@getlnx06 ~]# vi /etc/rc.local
# This script will be executed *after* all the other init scripts.
# You can put your own initialization stuff in here if you don't
# want to do the full Sys V style init stuff.
touch /var/lock/subsys/local
if test -f /sys/kernel/mm/redhat_transparent_hugepage/ then
echo never & /sys/kernel/mm/redhat_transparent_hugepage/enabled
使用上面的配置后必须重启操作系统才能生效，你也可以运行下面命令不用重启操作系统。You must reboot your system for the setting to take effect, or run the following two echo lines to proceed with the install without rebooting:
[root@getlnx06 ~]# echo never & /sys/kernel/mm/redhat_transparent_hugepage/enabled
[root@getlnx06 ~]# cat /sys/kernel/mm/redhat_transparent_hugepage/enabled
always madvise [never]
[root@getlnx06 ~]#
小知识点：1：从RedHat 6, OEL 6, SLES 11 and UEK2 kernels 开始，系统缺省会启用 Transparent HugePages ：用来提高内存管理的性能透明大页（Transparent HugePages ）和之前版本中的大页功能上类似。主要的区别是：Transparent HugePages 可以实时配置，不需要重启才能生效配置； 2：Transparent Huge Pages在32位的RHEL 6中是不支持的。Transparent Huge Pages are not available on the 32-bit version of RHEL 6. 3： Oracle官方不建议我们使用RedHat 6, OEL 6, SLES 11 and UEK2 kernels 时的开启透明大页（Transparent HugePages ）， 因为透明大页（Transparent HugePages ） 存在一些问题： 1.在RAC环境下 透明大页（Transparent HugePages ）会导致异常节点重启，和性能问题； 2.在单机环境中，透明大页（Transparent HugePages ） 也会导致一些异常的性能问题；Transparent HugePages memory is enabled by default with Red Hat Enterprise Linux 6, SUSE Linux Enterprise Server 11, and Oracle Linux 6 with earlier releases of Oracle Linux Unbreakable Enterprise Kernel 2 (UEK2) kernels. Transparent HugePages memory is disabled in later releases of Oracle Linux UEK2 kernels.Transparent HugePages can cause memory allocation delays during runtime. To avoid performance issues, Oracle recommends that you disable Transparent HugePages on all Oracle Database servers. Oracle recommends that you instead use standard HugePages for enhanced performance.Transparent HugePages memory differs from standard HugePages memory because the kernel khugepaged thread allocates memory dynamically during runtime. Standard HugePages memory is pre-allocated at startup, and does not change during runtime.Starting with RedHat 6, OEL 6, SLES 11 and UEK2 kernels, Transparent HugePages are implemented and enabled (default) in an attempt to improve the memory management. Transparent HugePages are similar to the HugePages that have been available in previous Linux releases. The main difference is that the Transparent HugePages are set up dynamically at run time by the khugepaged thread in kernel while the regular HugePages had to be preallocated at the boot up time. Because Transparent HugePages are known to cause unexpected node reboots and performance problems with RAC, Oracle strongly advises to disable the use of Transparent HugePages. In addition, Transparent Hugepages may cause problems even in a single-instance database environment with unexpected performance problems or delays. As such, Oracle recommends disabling Transparent HugePages on all Database servers running Oracle. 4：安装Vertica Analytic Database时也必须关闭透明大页功能。 参考资料：/solutions/46111http://www.soso.io/article/65143.html&&&&&　　免责声明：本文仅代表作者个人观点，与王朝网络无关。王朝网络登载此文出于传递更多信息之目的，并不意味着赞同其观点或证实其描述，其原创性以及文中陈述文字和内容未经本站证实，对本文以及其中全部或者部分内容、文字的真实性、完整性、及时性本站不作任何保证或承诺，请读者仅作参考，并请自行核实相关内容。&&&&&&为你推荐&&&&&&转载本文&UBB代码&HTML代码复制到剪贴板...&更多内容··········&&&&&&&&&频道精选&&&王朝女性&&|&&|&&|&&|&&|&&|&&|&&|&&|&&|&&|&&|&王朝分栏&&|&&|&&|&&|&&|&&|&&|&&|&&|&&|&王朝编程&&|&&|&&|&&|&&|&&|&&|&&|&&|&&|&王朝导购&&|&&|&&|&&|&&|&&|&&|&&|&&|&&|&王朝其他&&|&&|&&|&&|&&|&&|&&&&2005-&&版权所有&}