Bug 1294391

Summary: What is Large Memory System?
Product: Red Hat Enterprise Linux 7 Reporter: JINKOO HAN <jhan>
Component: Red_Hat_Enterprise_Linux-Release_Notes-7-en-USAssignee: Lenka Špačková <lkuprova>
Status: CLOSED CURRENTRELEASE QA Contact: RHEL DPM <rhel-docs>
Severity: high Docs Contact:
Priority: unspecified    
Version: 7.2CC: pbokoc, rhel-docs
Target Milestone: rcKeywords: Documentation
Target Release: ---   
Hardware: All   
OS: Linux   
Whiteboard:
Fixed In Version: Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2016-01-08 07:04:17 UTC Type: Bug
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:

Description JINKOO HAN 2015-12-28 01:41:16 UTC
Description of problem:

According to https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/7/pdf/7.2_Release_Notes/Red_Hat_Enterprise_Linux-7-7.2_Release_Notes-en-US.pdf, there has word as "system with large memory size".

How much bigger is large memory size? above 64GB? or how much of memory?


Version-Release number of selected component (if applicable):
- Red Hat Enterprise Linux 7.2 Release Note


How reproducible:
- it is document.


Steps to Reproduce:
1.
2.
3.

Actual results:
- write down specific memory size what large memory size is.


Expected results:


Additional info:

Comment 3 Petr Bokoc 2016-01-06 16:52:00 UTC
Hi,

I removed the mention of "large memory size" from the doc text - it wasn't the point of the message, it was just an aside and removing it doesn't change much.

FYI, there was no set size that was causing problems - it wasn't like "it was fine with 1 CPU as long as the memory was under 64 GB, above that kdump was always having issues". Using multiple CPUs prevents problems that *could* happen, and generally speeds up the process, depending on some other factors (e.g. target disk write speed). 

Of course, the more memory you have, the more time you save with the speedup - if adding a 2nd CPU made kdump twice as fast, then you might save 15 seconds on a 2GB RAM system and 1500 seconds on a 200GB RAM system.

Hope that clears it up.

- Petr

Comment 4 Lenka Špačková 2016-01-08 07:04:17 UTC
I have republished the Release Notes with the fixed description of Bug 1182376:
https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/7/html/7.2_Release_Notes/technology-preview-kernel.html