Questions about server hardware and software performance, or network performance.

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2
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1answer
1k views

How to achieve multiple NFS/TCP connections to the same server?

I'm trying to maximize the NFS/TCP bandwidth between a Linux client and a single NFS server over a 10Gbps link. Although each NFS mount has its own device (major/minor), everything comes down to a ...
0
votes
1answer
20 views

RAID1 very slow with LSI card and 2x Samsung EVO 850 drives

not sure if I'm checking it correctly, but here is what I have. Desktop, LSI 9260-8i card, see config below. 2x 500Gb Samsung 850 EVO drives. I also have Samsung 830 drive attached to motherboard ...
1
vote
0answers
5 views

SAS direct dual link connection to an embedded LSI Fusion-MPT controller

This is a hardware question. I have a dual-link SAS hard drive and a Intel S5000XVNSAS motherboard without the drive cage option. Recently, I bought a direct dual-link cable ...
3
votes
1answer
954 views

CentOS Tuned Equivalent For Debian

Running a few systems, a few are Debian which have been great. I have on the CentOS boxes tuned(tuned-adm) installed and setup for throughput. I searched all over Google and only found some articles ...
0
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0answers
8 views

PerfMon: Processor Queue Length - Random high spikes

I'm investigating alleged high CPU usage on one of our client's servers. After about 1 business day of "normal" activity, PerfMon is reporting the following values for Processor Queue Length, and I'm ...
0
votes
0answers
11 views

Postgres 9.3 maximal cluster size with streaming replication [duplicate]

First, I quote from https://wiki.postgresql.org/wiki/Binary_Replication_Tutorial: In Streaming Replication, the master and the standby have special processes called the walsender and walreceiver ...
0
votes
0answers
26 views

Server high memory and cpu - no leads

I've been asked to troubleshoot a server hosting our application at a client's facility. The client has complained to us on two separate occasions in the last week - week and a half. In one instance ...
7
votes
5answers
6k views

How can I replay Apache access logs back at my servers to do real world load testing?

I looked at http://serverfault.com/questions/2107/tools-for-load-testing-http-servers but I couldn't see how to replay my own existing logs in any of those tools. I have a bug that only occurs under ...
22
votes
3answers
7k views

PHP: What are the advantages of FastCGI over mod_php?

It was recently suggested to me that I use FastCGI with PHP. Now I went to the FastCGI page and read it but I don't really understand what the advantages are.
0
votes
1answer
914 views

Troubleshooting MySQL Performance Issues

Environment: 1 physical machine 8GB RAM some older Core2Duo CPU 1 HDD Windows Vista 64 bit 1 Virtual Machine 16 GB RAM 2 vCPUs Windows 7 64bit Both machines running MySQL 5.5.28 (64Bit) with ...
1
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2answers
1k views

Horrible PHP/MySQL Query Performance On Ubuntu Server 10.04

I just did a clear install of Ubuntu Server 10.04 with the standard LAMP config.. Then I made a small script to test insert speeds into a table with 3 columns. When I run the script on any of my ...
-1
votes
0answers
26 views

Fast disk filesystem setup for reading in linux? [closed]

General use file systems try to be everything for everyone. Fast reading, fast writing, journaling for fast recovery, etc Of course that these options come with compromise to achieve everything. I am ...
-1
votes
1answer
20 views

Measure traffic of streaming audio/video in whole office

I would like to measure the different traffic used in our office, specifically streaming of audio and video. I'm trying to assess whether there is any affect of people using streaming on our internet ...
0
votes
1answer
1k views

Performance Issue Between SQL and IIS on Seperate Machines

First time OP on serverfault, but an avid user of stackoverflow. We have two high-specification boxes, both running Windows Server 2008 R2 Standard. On one we have IIS 7.5, the other SQL Server 2008 ...
3
votes
1answer
913 views

BackupExec 12 + RALUS - VERY slow backups

We use Backup Exec 12 and the Remote Agent for Linux/Unix Servers (RALUS) to backup a large RHEL5 system. For various reasons we need to do a daily working set job. These working-set jobs run ...
3
votes
1answer
4k views

MySQL high CPU usage on small website

I have a small website hosted on a dedicated server (FreeBSD 9.2, MySQL 5.6.1 and php 5.5.5). The problem is that MySQL eats a lot of cpu resources even if the website have a few visitors. The ...
0
votes
3answers
3k views

Zabbix not collecting data

It's the first time that i install a Zabbix server on my dedicated server (debian 5). But zabbix cannot collect data from the server itself (no remote server, it's installed on the server i have to ...
4
votes
2answers
56 views

How to interpret values of Perfmon counter Hyper-V Hypervisor Virtual processor\CPU Wait time per dispatch

So there is a lot of guidance on the web that advises tracking the values of the Perfmon counter Hyper-V Hypervisor Virtual processor\CPU Wait time per dispatch as the nearest Hyper-V equivalent of ...
69
votes
13answers
15k views

Are networks now faster than disks?

This is a software design question I used to work on the following rule for speed cache memory > memory > disk > network With each step being 5-10 times the previous step (e.g. cache ...
-2
votes
0answers
24 views

Hardware requirements for 500 - 2000 concurrent connections to LAMP+ [duplicate]

A hint where to look, where to start... Software used for real time auction web project Apache 2.4.6 (forked) +(mod_pagespeed) PHP FastCGI v5.4.16 PHP-APC cache MemcacheD +shared sessions with PHP ...
-4
votes
1answer
31 views

mysql hot add memory

Is it possible for currently running jobs in MySQL to utilize memory that's been hot added? It looks like when memory is hot added to the VM the currently running jobs are not utilizing the additional ...
-1
votes
1answer
20 views

Synchronize Staging Server and Live Server [closed]

We have staging and live server at our office. Where Live code and DB changes are far more advanced than staging one.This application developed under php and DB is mysql. Earlier we used to work in ...
0
votes
1answer
84 views

UFS wedge : “Out of journal space!” - how to tune? (FreeBSD)

I'm running FreeBSD 9.2p13 with UFS and journaled softupdates. Does anybody know how to tune softupdates journal on UFS? There are no suitable information in handbook, man pages or sysctl ...
1
vote
1answer
717 views

Oracle: TRUNCATE sometimes takes ages

Usually, truncating a table takes 5-10 seconds. But when several people work on the same DB instance (but different tables), the operation can take more than an hour. How do I debug this?
2
votes
3answers
816 views

Is it ok to team NIC's from different vendors together in VMware ESX?

I want to achieve the best performance with my two servers (SAN and ESX). I have good RAID (LSI, SASes), that is showing 1GB/s result, so the bottleneck now is network part since I have only two NICs ...
0
votes
2answers
298 views

MySQL Database Problems - Growing too quick, Performance

I have some problems with my database setup: The MySQL Database is written to every few seconds and it grows in size very quickly. My disk space is limited though, so I have to work around that. ...
0
votes
1answer
172 views

epoll timeout configuration in lighttpd

Is there a configuration option to tune epoll timeout in lighttpd? I'm developing an embedded Linux (2.6) device, with lighttpd 1.4.30. And I'm observing the following issue: even when the system is ...
11
votes
8answers
12k views

Troubleshooting a “slow” network

We've all had a complaint that the "network" is "slow" at some point: might be localized to one room (switch) or one computer, might just be Internet (DNS? Browser issue?), might be just one ...
1
vote
4answers
8k views

How long does it take to rebuild a drive in a RAID 6?

I'm building a 7-disk RAID 6 array on a DELL MD3000 DAS box. My top priority is storage space, so I'd like to use 2TB drives -- but I'm worried about how long it will take to rebuild a failed disk. ...
0
votes
0answers
66 views

Python libraries slow to load from NFS mount point

Several of our computers are diskless, and they load their Python libraries from an NFS mount point across the network. This means it can take up to three minutes to start up a Python process that ...
3
votes
2answers
281 views

Fastest SSL cipher implementation for Nginx if strength is NOT needed?

I have a use case that is the inverse of most: I'd like to implement very weak SSL ciphers in the name of performance, with the option to fall back to stronger ciphers if the client requests it. ...
0
votes
1answer
41 views

Does PostgreSQL perform on Windows as well as on Linux

This topic was brought up in 2011, and the consensus was that there were design considerations that would give PostgreSQL a leg up on Linux. It is now 2015, has that changed? If there are things that ...
3
votes
2answers
2k views

Find current IOPS usage of EBS volume from my application on AWS EC2

I am relatively new to AWS and disk performance. I am trying to figure out how much provisioned IOPS does my application need to perform well. Currently My PHP and MySQL application is hosted on EC2 ...
0
votes
0answers
23 views

Troubleshooting high load average

We have a cluster of Centos 6.5 servers that run Java on them. These servers connect to a cluster of MongoDBs quite frequently. On the Java cluster, we are seeing high load averages but CPU ...
0
votes
0answers
7 views

'nc' using ~100% CPU when transferring a FIFO file [migrated]

On the server which is always connected I’m using this in a crontab: @reboot nc -k -l 1234 < /tmp/fifo.fifo On the client which is not always on the network or switched on I’m using this ...
7
votes
4answers
7k views

Gigabit ethernet generally faster than Firewire 800?

If I want to transfer a large file between two computers, which are connected via LAN, would going through the network (setup as gigabit ethernet) be faster than using a direct Firewire 800 connection ...
0
votes
0answers
49 views

Is it better to store the MySQL database directory on a separate RAID 1 device?

We have a Linux server with a RAID 1 using two HDDs on which runs a Apache server managing multiple sites and some other services that interact intensively with the databases and produce massive ...
1
vote
2answers
1k views

NFS Over OpenVPN: Top Performance Boosters

I have two VPS's - One is running 2008 Server R2 and the other is a Ubuntu 12.04 installation. I am using the Windows VPS for RD sessions for Quickbooks and a couple other apps and using the Ubuntu ...
0
votes
1answer
282 views

Postfix mail server (outbound) strategy

I am about to setup a web application that consists of 2 app servers (running php/apache) and 2 db servers (ubuntu slices on slicehost). The application will be sending approximately 5000 emails a ...
0
votes
1answer
1k views

Why is hash join slow in postgresql 9.1?

I transfered my DB from Postgresql 8.4 to new server with Postgresql 9.1. Size of DB is 9.9GB Data directory is situated on ssd 60GB disk. And server has 16GB RAM and 16 proccessor cores. But today ...
3
votes
1answer
1k views

Very poor disk performance on KVM node - mdadm raid10

For a long period of time, i'm experiencing performance issues on CentOS servers that are used for KVM virtualization. I'm running software RAID-10 with 4 disks (Seagate ST2000DM001, 2TB, 7200rpm ...
0
votes
2answers
120 views

email sending speed - how to improve

I am maintaining a server to send email mailings (no spam, of course). The current speed of this machine is approx. 2000 emails per hour. (edit: actually I did a test mailing today, removing the ...
0
votes
0answers
17 views

Poor memory performance on intel avoton?

I have 12 of these supermicro A1SA2-2750F boards that I'm playing around with in order to compare them to Dell's C5220s but I'm seeing consistent poor memory performance. Just curious if anyone's ...
2
votes
2answers
2k views

How to improve Varnish performance?

We're experiencing a strange problem with our current Varnish configuration. 4x Web Servers (IIS 6.5 on Windows 2003 Server, each installed on a Intel(R) Xeon(R) CPU E5450 @ 3.00GHz Quad Core, 4GB ...
1
vote
1answer
91 views

Linux fixed file size copy from Windows Server 2012 NFS share

Company is in the process of switching from hosting MongoDB on windows server 2012 to hosting on linux(ubuntu 14.04) Current backup and restore strategy involves copying all the data files via ...
0
votes
1answer
1k views

htcacheclean doesn't seem to be cleaning the cache

I'm running mod_cache with apache 2 on a fairly high traffic'd site. I've set the htcacheclean to run in demon mode every 10 minutes to keep the cache at 4GB. It's currently at 15GB and doesn't seem ...
3
votes
1answer
1k views

Very low throughput on 10GbE network

I have two Linux machines, each equipped with a Solarflare SFN5122F 10GbE NIC. The two NICs are connected together with an SFP+ Direct Attach cable. I am using netperf to measure TCP throughput ...
0
votes
0answers
35 views

Apache and JBoss mod_cluster speed up reload

As an alternative to this question, is it possible to decrease the amount of time that it takes for the Apache (httpd) server to pick up the JBoss servers after the Apache server reloads? As of right ...
1
vote
1answer
906 views

interpreting IOPS these Bonnie++ and iostat results

I am looking to interpret the IOPS from a few runs of bonnie++ using iostat simultaneously and using the benchmarking from this post: Can I determine IOPS on a disk array using bonnie++? bonnie++ ...
6
votes
1answer
57 views

postfix performance with lists in main.cf

For defining a list of items to assign to many different options in postfix, you can either use a comma separated list like this: relay_domains = example.com,example.net,example.org or a hash map ...