Performance tuning is the process of modifying a system to improve its efficiency. This is also known as optimizing.

learn more… | top users | synonyms

0
votes
0answers
16 views

Task Manager shows high kernel time

Foreward: Hardware: dual-socket Intel Xeon, 128gb memory, hardware RAID-1 SSD OS: Windows 2012 R2 Standard w/ Remote Desktop Services The Task Manager for one of our terminal/application servers ...
1
vote
1answer
30 views

TCP retransmission delays - lost acks

Maybe somebody will be able to help me out with this. I'm trying to find out if there is anything that can be optimized server-side to reduce delays in case of packet loss. Environment: Windows 2012 ...
0
votes
0answers
22 views

Why are httpd processes spending increasing amounts of time in logging state?

I'm running an Apache 2.2 web server. When stress testing I notice that I cannot increase load beyond a certain number of simultaneous connections. The strange thing is that I do not seem to have ...
0
votes
0answers
6 views

What does the “web transaction” mean in new relic transactions report?

In new relic transaction report breakdown table, I often see an entry called "web transaction" and then there are various DB calls and cache calls. Initially I assumed that it's the time my script is ...
0
votes
1answer
26 views

JBOSS AS 7 monitoring Paramaters

We are using JBOSS AS 7 in standalone mode to run our web application. Our user base is around 1000 users and we have 4 instances of a JBOSS running on 4 RHEL6 machines behind a load balancer. ...
3
votes
2answers
311 views

Optimizing storage of 10-20 million files on RAID5 (currently using LVM+XFS)

Although I've browsed some of the questions here, I think every situation is different and maybe requires a totally different solution. What I have now: Linux software RAID5 on 4x4TB enterprise HDD ...
-2
votes
1answer
42 views

Analyzing server performance [duplicate]

Analyzing server performance Hi we have recently finished work on one ecommerce site which is built on opencart 2.x and site has around 1k products. The site is currently running on VPS server. from ...
0
votes
0answers
25 views

Definition of CPU Ready for vmware ESXi host compared to CPU Ready for a guest?

We had a guest with poor performance. CPU Usage and CPU Ready for the guest was within normal range. For the host the CPU Usage were normal (70%), but the CPU Ready for the host seems to correlate ...
1
vote
1answer
31 views

How do you measure IMAP performance?

We have a mail server built on top of a Gluster distributed filesystem. While this has proven to be fairly easy to set up and quite stable, the performance of our webmail has been quite slow. So now I ...
1
vote
1answer
124 views

How to optimize throughput on a linux NAT/router?

I am trying to use an old Fujitsi RX300S2, with a quad core Intel Xeon CPU @2.80GHz as a Gitabit NAT router, it has a dual gigabit NIC on board over PCI-X. The router will also forward multicast ...
0
votes
0answers
12 views

How can I get a nginx & php server to use much more system resources?

I'm running a local setup. Crunching some largish 100mb json files via php running on nginx. I'm also doing some mysql stuff, checking through tables with about 90k rows, matching data from the json ...
0
votes
0answers
62 views

Mongodb, we can't go over 100 insert/sec on 200iops HDD

Thanks in advance for your help, we get a strange behaviour in mongodb. So we have a cluster of 20 shards, each composed of 1 master and 2 slaves. This database has a heavy load of write only. However ...
1
vote
0answers
174 views

Identifying bottleneck with nginx VPS load testing

I'm trying to optimize a Digital Ocean droplet (512mb), testing using loader.io I'm testing on my homepage, which is HTTPS / PHP. I setup FastCGI page cache, which got me from 100 req/sec to 2,000 ...
0
votes
1answer
404 views

Mysql innodb_buffer_pool_size in relation to innodb_buffer_pool_instances

I run a virtual server with an Owncloud installation on it. Now Owncloud has the problem that the way it's developed at the moment, each file upload causes a little MySql overhead. So is very ...
1
vote
0answers
34 views

Persist statistics data from Postgres' stats_temp_directory on demand

We are investigating I/O load in one of our VMs and possibilities to optimize it and it showed that most of the load is generated by the stats collector of PostgreSQL. It jumps between 3,5 and 6,5 MB/...
14
votes
2answers
1k views

Virtualization - Ten 1Gbps links or one 10Gbps link? (Performance)

I have a machine that has several VM's (5) and 3 physical networking cards (with each 2 ports), with a total of six 1Gbps ethernet ports. I have a SPF-capable switch, having a total of 48Gbps ...
3
votes
0answers
37 views

what are the memory impacts of increasing a NIC's ring buffer?

What impact (if any) does NIC ring buffer tuning (e.g. via ethtool -G eth0 …) have on system memory utilization? For example, does increasing the ring buffer consume more RAM? And if so, how much? Or ...
0
votes
1answer
56 views

Current Number of Requests per Second with Apache 2.4

I know how to test the maximum number of requests per second with tools like apache bench and httperf. But is there a way to see the average number of requests per second a live server is currently ...
32
votes
2answers
4k views

Why is my bare-metal 16x 2.93GHz cores computer performing poorer than a VPS with 4x 2.5GHz cores?

I have a written a piece of multi-threaded software that does a bunch of simulations a day. This is a very CPU-intensive task, and I have been running this program on cloud services, usually on ...
2
votes
1answer
128 views

What does sunit=0 and swidth=0 mean for XFS file system?

I created an XFS file system using default parameters at the time of creation of a system. Now looking at the output of xfs_info, it show 0 for the values of sunit and swidth. I can't seem to find ...
2
votes
0answers
33 views

Perf crashing my RH

We are running perf on a 2.6.32-358.56.1.el6.x86_64 on an 8-core, dual socket machine. We have CPU iso on CPUs 1-31 (all except for 0), and our application is using CPUs 1-31. A few seconds into ...
2
votes
0answers
49 views

Google Cloud Long TTFB

Google cloud seems to be having much longer TTFB than they specify in their documentation for cloud storage. You can see from this WPT result that it varies from 500 to 700 MS. The documentation here ...
2
votes
4answers
3k views

Slow write Performance with HP H240 HBA using internal Storage with Raid 5 SSD's

I am having a HP Proliant DL 160 Gen9 Server with a HP H240 Host Bus Adapter. 6x 1 TB Samsung SSD's configured in a raid 5 directly using the internal storage of the machine. After installing a VM on ...
1
vote
0answers
34 views

mod_pagespeed css shown render blocking?

I've already found this topic concerning my problem and figured out Google is about to discuss a fix of the blocking js. However, could somebody please check out my client's site squarecard.de with ...
3
votes
0answers
200 views

Is RSS (receive side scaling) in Windows considered unstable?

When asking a customer to enable RSS in their data center to improve network performance (very high UDP packets-per-sec rate), I was told that they generally turn it off, because after various ...
3
votes
1answer
424 views

Preventing PHP-FPM from crashing under light load

I'm getting a DoS attack on a wordpress site that I host. 173.192.109.118 - - [30/Sep/2015:22:31:36 +0000] "POST /xmlrpc.php HTTP/1.0" 499 0 "-" "Mozilla/4.0 (compatible: MSIE 7.0; Windows NT 6.0)" ...
0
votes
2answers
64 views

Performance testing LAMP-Cluster - How to find bottle neck?

I have set up a cluster of 3 nodes running a LAMP-Application with HAProxy doing the load balancing. Now I would like to optimize and load test the system. Therefore I am unsing jmeter-ec2 which ...
-2
votes
1answer
32 views

Find a load on my Web Server [duplicate]

As requested, I am asking the question here. Is there a way to find a load on my web application server without a load / stress testing? I have deployed my application in the Apache Tomcat server. ...
0
votes
1answer
1k views

How to raise max no of file descriptors for daemons running on Debian Jessie?

I'm playing with pgBouncer as a connection pooling system for PostgreSQL. My system is a 12-core with 64GB RAM and 1Gbps network interface running Debian 8.1. Now I want to raise the limit for open ...
8
votes
1answer
335 views

How do I tell how close I'm getting to somaxconn?

The sysctl option net.core.somaxconn defaults to 128 (on our systems) but can be raised. What exactly is this limit measuring and capping? How do I find out how close I am to the limit? Context: I ...
2
votes
1answer
929 views

Nginx performance when running multiple instances on the same machine

I'm trying to understand the performance impact of having multiple nginx instances (masters) running on the same machine, rather than having them all load into a single instance using different server ...
3
votes
1answer
1k views

Does 'tuned' need to keep running?

On my CentOS 7 systems, I use tuned-adm to set a profile appropriate to the environment during configuration, but after that, I never subsequently change that profile. It seems that the tuned system ...
-1
votes
0answers
9 views

How to identify underutilized servers? [duplicate]

How to identify if the servers are underutilized and CPU/RAM resources can be decreased? Servers are virtual running on VMware. I thought of MAP Toolkit for collecting performance data and then ...
2
votes
1answer
199 views

Bind9 recursive queries have intermittent very long response times

I'm running BIND 9.8.1-P1 caching server on Ubuntu 12.04 LTS on kernel 3.2.0-86-generic-pae. I've been banging my head against the wall trying to figure this out for weeks and I just have no idea ...
3
votes
0answers
95 views

Investigating Citrix app server “slowless”

Currently have a client stating that the 5 users on a 2cpu, 4gb mem app server are experiencing slowness and often, locking up for moments at a clip. Framework is a VM running in vSphere 5.5 [intel ...
1
vote
0answers
46 views

How to track down bad performance on an api-server

If my api-server shows bad performance, such as high cpu - can this be blamed on the service or on the server? If a regular app-server shows bad performance, all I can do is track down the methods ...
1
vote
0answers
91 views

Maximum Network throughput for SWIFT storage

I have a SWIFT cluster deployed as part of Openstack which is currently giving me a max throughput of 95 MBS(Megabytes per second). There are 6 proxy servers and 6 storage nodes with replication ...
1
vote
0answers
186 views

Advice Tuning my server

as many others I Learn many info from you in the past and now I manage to run server independently , now I am new to sql tuning and I been searching around the web a while now and tuning seems to be a ...
1
vote
2answers
296 views

PHP5-FPM pm.max_children affect RAM or CPU+RAM?

Recently inherited a Nginx+PHP5-FPM server, and I'm learning and trying to optimize PHP5-FPM settings. Server info: 4 CPUs (8 threads) 7.5 GiB RAM PHP5-FPM info: pm.max_children = 5 pm....
14
votes
3answers
2k views

Virtual machines and I/O heavy workload, is it ever sane?

I have seen on numerous virtualization services (Azure) and products (vmware,kvm,hyperv) I/O and system stalls under heavy I/O workload. My questions are: Is it ever sane to use a Virtualized ...
0
votes
1answer
1k views

How to resolve '[info] server seems busy' from apache server logs?

I've seen this question asked a few times but it hasn't had any real answer; so I've decided to post my resolution. The below info message can be seen in the apache error.log: [info] server seems ...
0
votes
1answer
80 views

Percona: What are the implications of changing repl.commit_order?

I'm currently doing some trials of Galera Cluster with Percona 5.6. I've progressed to testing a 2 node cluster on baremetal. With repl.commit_order set to 0 (off) the TPS performance as measured with ...
0
votes
2answers
56 views

how to find the highest IO consumer on a disk? [closed]

Can some one help to find highest IO consumer on each individual disks? i.e Which process consumes the most IO on /dev/sda, the highest IO consumer on /dev/sdb etc.
2
votes
1answer
293 views

ESXi very slow with WD reds

I have a small company and we offer tech support to small companies. I've been using the HP Gen8 MicroServer in most of them as a replacement of homebuilt computers for some time. Sometimes customers ...
4
votes
4answers
3k views

MySQL taking too much CPU

Below is my .cnf file and if I see my CPU consumption 99.99% of it my the mysqld commands. The MySQL server is connected from remote machines that update data in it frequently, but I make sure that ...
8
votes
2answers
20k views

How To Tune Apache on Ubuntu 14.04 Server

Currently on my Apache 2 (Apache 2.4.7 to be exact) on Ubuntu 14.04, I have this setting: /etc/apache2/mods-enabled/mpm_prefork.conf <IfModule mpm_prefork_module> StartServers ...
7
votes
1answer
239 views

What do users see when Apache reaches MaxClients?

Occasionally, in my Apache error log, I will find: [error] server reached MaxClients setting, consider raising the MaxClients setting I've purposely lowered MaxClients in the past (to 60) due to ...
0
votes
1answer
92 views

Does Apache mod_status give any insight to tuning Apache config?

Does the Apache mod_status output give any insight to tuning Apache prefork config? For example, using Apache's mod_status, I figured out that My server gets 3 requests/sec average, the range is 2-...
2
votes
1answer
299 views

NFS performs ways worse than SSHFS, how can I debug?

Situation: zfs server over 10GbE p2p at 192.168.201.1 running omnios, debian client at 192.168.201.2. The nfs performs fairly well on big files but horribly slow on small ones. For instance, cp -r /...
0
votes
2answers
104 views

nginx can't execute many requests

I have a question about nginx tune. I have an application which I want execute 200 times every second. I created bash file and used wget with bqO switch for execute. But it has a problem. When the ...