Login or Register to Ask a Question and Join Our Community


Red Hat

%memused is high

Login to Discuss or Reply to this Discussion in Our Community

 
Thread Tools Search this Thread
Operating Systems Linux Red Hat %memused is high
# 1  
Old 02-20-2017
%memused is high
All

I see cpu and memory usage are under control, only cache gets high upto 99% using sar -r command

I did echo3 and cleaned the drop caches

do we need to monitor this , why my application going high upto 99.8% memused in sar command , this is cache memory which is going high

will this cause any performance issues like slowness ?

I understand Kernel should manage this , so do I need to clean up manually ?

Please suggest
# 2  
Old 02-20-2017
Quote:
Originally Posted by anil529
will this cause any performance issues like slowness ?
No, on the opposite, using your RAM as cache is expected to improve your system performance.
Quote:
I understand Kernel should manage this , so do I need to clean up manually ?
No. Unused RAM is wasted RAM.
This User Gave Thanks to jlliagre For This Post:
anil529
# 3  
Old 02-21-2017
Thank you jlliagre

What I noticed could be other coincidence
App was responding toooo slow
CPU and memory were fine
Only cache is close to the ram size in terms of %memuser it is 99.8 %

So I dropped cache and then users were able to login app and work

This is happening once in a week

Any suggestions to look at something else other than cache for slownesss ?
Is 99.8% cache usage ok ?
# 4  
Old 02-21-2017
You shouldn't focus on a single metric and assume it is the key to performance. Better to provide everything useful for us to figure out what is going on on your system (hardware description, sizing, application used, full statistics output). In particular, not telling the fact users were unable to login in your first post didn't help.
This User Gave Thanks to jlliagre For This Post:
anil529
# 5  
Old 02-21-2017
Code:
# lscpu
Architecture:          x86_64
CPU op-mode(s):        32-bit, 64-bit
Byte Order:            Little Endian
CPU(s):                4
On-line CPU(s) list:   0-3
Thread(s) per core:    1
Core(s) per socket:    1
Socket(s):             4
NUMA node(s):          1
Vendor ID:             GenuineIntel
CPU family:            6
Model:                 62
Model name:            Intel(R) Xeon(R) CPU E5-2643 v2 @ 3.50GHz
Stepping:              4
CPU MHz:               3499.810
BogoMIPS:              6999.99
Hypervisor vendor:     VMware
Virtualization type:   full
L1d cache:             32K
L1i cache:             32K
L2 cache:              256K
L3 cache:              25600K
NUMA node0 CPU(s):     0-3




paging  getconf PAGESIZE
4096


avg-cpu:  %user   %nice %system %iowait  %steal   %idle
           2.85    0.05    0.51    0.07    0.00   96.53

Device:            tps    kB_read/s    kB_wrtn/s    kB_read    kB_wrtn
sdc               5.00       200.43        24.87   98583358   12234372
sda               0.47         1.97        26.50     970878   13033637
sdb               0.77        23.65        61.56   11632840   30280515
dm-0              0.08         1.41         0.15     692727      75933
dm-1              0.09         0.10         0.25      50168     122304
dm-2              5.84       224.08        86.44  110215182   42514888
dm-3              0.02         0.24         0.04     119390      21436
dm-4              0.09         0.05         0.47      26330     231148
dm-5              0.01         0.05         0.02      26430       9073
dm-6              0.00         0.01         0.00       4077       2060
dm-7              0.12         0.04         0.46      17428     225745
dm-8              0.17         0.01        24.98       3242   12288489
dm-9              0.02         0.01         0.07       5800      35801



Application is used to enter data and tracking , graphical representation



Moderator's Comments:
Mod Comment Please use CODE tags as required by forum rules!
Last edited by RudiC; 02-21-2017 at 12:44 PM.. Reason: Added CODE tags.
# 6  
Old 02-21-2017
First off, you are running a hypervisor -VMware. No problems, but I do not understand the cpu queue length on a system that is doing almost nothing.

If your output ran from the base system, then nothing is going on system-wide.
Is this the base or one of the virtuals?

I am not well-versed with VMware, but there is a toolset, I believe, that will show what is going on on all of the virtuals and the base system as well.
This User Gave Thanks to jim mcnamara For This Post:
anil529
# 7  
Old 02-21-2017
Thank you very much again

Yes I am on VMWARE , don;t have access to base
Login or Register to Ask a Question

Previous Thread | Next Thread

7 More Discussions You Might Find Interesting

1. Solaris

High availability

hi guys I posted problem last time I didn't find answer to my issue. my problem is as below: I have two servers which work as an actif/standby in high availability system. but when i use command HASTAT -a i have the following message: couldn' find actif node. the servers are sun... (1 Reply)
Discussion started by: zineb06
1 Replies

2. Red Hat

CPU is high

Hi , We found CPU is high due to python process .Is this something that Oracle team should look on or Unix team has to work on it ?Could you please advise use of python process ? top - 12:03:03 up 43 days, 15:11, 5 users, load average: 1.53, 1.33, 1.23 Tasks: 126 total, 3 running, 123... (12 Replies)
Discussion started by: Maddy123
12 Replies

3. Shell Programming and Scripting

what would a script include to find CPU's %system time high and user time high?

Hi , I am trying to :wall: my head while scripting ..I am really new to this stuff , never did it before :( . how to find cpu's system high time and user time high in a script?? thanks , help would be appreciated ! :) (9 Replies)
Discussion started by: sushwey
9 Replies

4. Red Hat

apache high cpu load on high traffic

i have a Intel Quad Core Xeon X3440 (4 x 2.53GHz, 8MB Cache, Hyper Threaded) with 16gig and 1tb harddrive with a 1gb port and my apache is causing my cpu to go up to 100% on all four cores heres my http.config <IfModule prefork.c> StartServers 10 MinSpareServers 10 MaxSpareServers 15... (4 Replies)
Discussion started by: awww
4 Replies

5. Solaris

pswch/s too high

Hello Unix gurus, I have a Solaris 8 system on which since last few days we are noticing 0% idle state. When I checked with sar utility, I saw that process switching is very high. The output of sar -w is pasted below: sar -w 3 20 SunOS bdspb306 5.8 Generic_108528-18 sun4u 06/24/08 ... (0 Replies)
Discussion started by: akashgulati
0 Replies

6. Shell Programming and Scripting

Please Help me with this ..High Priority!

Hi, I am a nw bie to Schell Scripting, i have a same king of requirement as posted above. my input file is also a log file as below..... 28.05.2008 07:02:56,105 INFO Validation request recieved 28.05.2008 07:03:57,856 INFO 0:01:13.998 Response sent with: <?xml version="1.0"... (0 Replies)
Discussion started by: balaji_gopal
0 Replies

7. UNIX for Advanced & Expert Users

Sun: High kernel usage & very high load averages

Hi, I am seeing very high kernel usage and very high load averages on my system (Although we are not loading much data to our database). Here is the output of top...does anyone know what i should be looking at? Thanks, Lorraine last pid: 13144; load averages: 22.32, 19.81, 16.78 ... (4 Replies)
Discussion started by: lorrainenineill
4 Replies
Login or Register to Ask a Question