diff options
author | Costa Tsaousis (ktsaou) <costa@tsaousis.gr> | 2018-02-24 14:27:42 +0200 |
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committer | Costa Tsaousis (ktsaou) <costa@tsaousis.gr> | 2018-02-24 14:27:42 +0200 |
commit | 9b710aca181e75d4a7bada7c029cebf9963b23cc (patch) | |
tree | 9495d5786ab1a3d9f5d2edad6c821e82d4b74ab4 /web/dashboard_info.js | |
parent | 19a10536563fe35ebe3e6d481936b06ffe4f9156 (diff) |
transparent hugepages monitoring; #3462
Diffstat (limited to 'web/dashboard_info.js')
-rw-r--r-- | web/dashboard_info.js | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/web/dashboard_info.js b/web/dashboard_info.js index e97de0d7cc..e2eafd52fb 100644 --- a/web/dashboard_info.js +++ b/web/dashboard_info.js @@ -418,6 +418,10 @@ netdataDashboard.submenu = { info: 'Kernel Same-page Merging (KSM) performance monitoring, read from several files in <code>/sys/kernel/mm/ksm/</code>. KSM is a memory-saving de-duplication feature in the Linux kernel (since version 2.6.32). The KSM daemon ksmd periodically scans those areas of user memory which have been registered with it, looking for pages of identical content which can be replaced by a single write-protected page (which is automatically copied if a process later wants to update its content). KSM was originally developed for use with KVM (where it was known as Kernel Shared Memory), to fit more virtual machines into physical memory, by sharing the data common between them. But it can be useful to any application which generates many instances of the same data.' }, + 'mem.hugepages': { + info: 'Hugepages is a feature that allows the kernel to utilize the multiple page size capabilities of modern hardware architectures. The kernel creates multiple pages of virtual memory, mapped from both physical RAM and swap. There is a mechanism in the CPU architecture called "Translation Lookaside Buffers" (TLB) to manage the mapping of virtual memory pages to actual physical memory addresses. The TLB is a limited hardware resource, so utilizing a large amount of physical memory with the default page size consumes the TLB and adds processing overhead. By utilizing Huge Pages, the kernel is able to create pages of much larger sizes, each page consuming a single resource in the TLB. Huge Pages are pinned to physical RAM and cannot be swapped/paged out.' + }, + 'mem.numa': { info: 'Non-Uniform Memory Access (NUMA) is a hierarchical memory design the memory access time is dependent on locality. Under NUMA, a processor can access its own local memory faster than non-local memory (memory local to another processor or memory shared between processors). The individual metrics are described in the <a href="https://www.kernel.org/doc/Documentation/numastat.txt" target="_blank">Linux kernel documentation</a>.' }, @@ -702,6 +706,14 @@ netdataDashboard.context = { info: '<b>Reclaimable</b> is the amount of memory which the kernel can reuse. <b>Unreclaimable</b> can not be reused even when the kernel is lacking memory.' }, + 'mem.hugepages': { + info: 'Dedicated (or Direct) HugePages is memory reserved for applications configured to utilize huge pages.' + }, + + 'mem.transparent_hugepages': { + info: 'Transparent HugePages (THP) is backing virtual memory with huge pages, supporting automatic promotion and demotion of page sizes. It works for all applications for anonymous memory mappings and tmpfs/shmem.' + }, + // ------------------------------------------------------------------------ // network interfaces |