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

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1answer
4 views

slow file server with contradictory values for CPU and CPL in atop

I've got a fileserver (centos 6.3) that slowed down suddenly earlier today. The cluster that mounts it could access other NFS mounts without a problem, but the access to this one was VERY slow. ...
1
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0answers
45 views

NGINX using 100% of the server CPU when testing with Blitz.io

I'm facing an issue here and after four days of looking around I decided to ask for some help here, after all a million heads can think a lot better than one. I have a Ubuntu 14.04 server setup with ...
1
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0answers
24 views

Improve read performance on ext4 on Centos with software raid1? [duplicate]

I'm running a number of MongoDB nodes on dedicated servers running Centos6. Each machine has two SSDs which I have in Raid1 with two logical partitions: # df -h Filesystem Size Used Avail Use% ...
1
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1answer
25 views

Strange Disk Benchmarking results for our storage, how to explain? [on hold]

I recently tested the storage we got from our hosting provider. I don't know what raid config or how many disks the storage contains of. I used Atto Disk Benchmark which sends smaller and bigger ...
2
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2answers
77 views

Linux virtual memory tuning to workaround disk I/O issue

I am having a problem with a Linux server that it is writing to much to disk, thus I am having a slow response time due to a big IO wait. I already check smart values for the disks and are OK. This is ...
2
votes
1answer
854 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 ...
2
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2answers
2k views

High disk I/O activity in CentOS server

I have about 16 websites in a CentOS dedicated, and I am having some problems on high traffic hours, it seems to be a high disk I/O activity causing a general slowdown. I've installed atop and this ...
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0answers
49 views

Slow site, most time spent Blocking/Connecting [on hold]

My site is based on user-submitted content, meaning that users can upload images, etc. The problem is, my website loads extremely slowly on first load (before it caches). For example, here is the ...
1
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2answers
29 views

What is the difference between truss -D and truss -E?

I am currently analyzing a command on Solaris that reads from a file and has very low performance. The truss -D commands shows me read system calls taking up to 0.03 seconds, but when I use truss -E, ...
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0answers
26 views

Good Internet connection, but websites load slowly or not at all and internal web server presents same issue to outside users

Lately, users in my organization have been having problem accessing web pages. The browser status bar will say "Waiting for [site]" or "Downloading...", but pages never load, or only load partially ...
1
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1answer
29 views

Ubuntu Server 14.04LTS Swappiness for server with 16GB memory

(don't worry I'm not asking what my setting should be, asking for the theory behind some conflicting advice I've read) My application is one that is lightweight and not under much load, but needs to ...
-2
votes
2answers
64 views

fastest way to transfer small files (faster than scp) [closed]

Scp is quite slow for transferring individual files. What is the quickest way to do this? The reason I need speed is not because I have a large number of files to transfer. I just want the individual ...
1
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2answers
2k views

Per process I/O accounting on AIX

Is there a way of getting per process I/O statistics on AIX, i.e. to get current disk I/O rate of a process? Commands like iostat, nmon, topas etc. can't display such data. Filemon also doesn't help. ...
1
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1answer
48 views

Website performance sluggish - High CPU and Disk Usage

Over the past couple of days my website's performance has been very sluggish, with queries taking a lot of time to execute. My CPU usage hit around 100% 4 times this week. Here is the output of top at ...
0
votes
1answer
900 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 ...
1
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0answers
61 views

Is it normal for uploads on ADSL to make the connection unusable (> 4000ms latency)? [migrated]

I have an ongoing saga with my internet connection; where the latency periodically goes through the roof. In most cases, this seems to coincide with something uploading data. I'm not having a lot of ...
0
votes
1answer
23 views

What is the counter type for Linux's /sys/block/$DEVICE/stat

What are the counter types for /sys/block/$DEVICE/stat? $ cat /sys/block/sda/stat 8323741 42381356 464031898 19207478 1940738 49062039 408122282 79935459 0 22315734 99172579 Specifically, ...
1
vote
2answers
973 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 ...
0
votes
1answer
50 views

Measure Dedicated Server Performance

I run an online video streaming site and keep getting more and more dedicated servers. Our business traffic fluctuates on an annual cycle which allows us to scale back our dedicated servers during the ...
0
votes
1answer
26 views

PostgreSQL queries slower than before?

I am using PostgreSQL 9.3 server on my production server. Everything had been working fine for the past couple of months. But since the past week or so, PostgreSQL seems to have becomes very slow with ...
0
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0answers
33 views

What happens on an SQL Server when a snapshot is taken by VMWare?

Recently I saw in our SQL Server logs that a snapshot could not be taken at the specific time and he retried it later on. During that timespan we had a huge performance problem. Besides the SQL Server ...
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votes
1answer
340 views

Would cPanel or Plesk slow down my site/server? [closed]

My senior sysadmin told me that if I install cPanel or Plesk (or other panel) on a client's machine as it would slow down the server/site (WordPress on LAMP). This doesn't seem to make logical or ...
0
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0answers
26 views

Capacity planning of messenger server [duplicate]

This is regarding a messenger server being developed. This will have thousands of users connected and will be able exchange messages. Users will also be able to send messages intended for multiple ...
0
votes
1answer
72 views

How to solve performance problems with VMware ESXi 5.5 on old Dell PowerEdge 2900 hardware [closed]

I have a couple of old Dell PowerEdge 2900 servers that have come free and I would like to use them to host a mail server cluster. They are a bit old, but have been running workhorses for a while, ...
3
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2answers
181 views

iozone: 5 concurrent threads random read of 300K blocks does more ops/s than using only one thread, what could be the underlying reason?

The partition is in RAID1 using software RAID. Command line used: iozone -s 190g -r 300k -O -b test_file OPS Mode. Output is in operations per second. ...
0
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0answers
89 views

Troubleshooting poor Windows Server performance

I have two Windows Servers. One is used as the Gated Check-In build server and the other is planned to replace it. However, the second server demonstrates poor performance despite having superior ...
2
votes
1answer
2k 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 ...
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0answers
76 views

Cannot set 1G speed on 10G nic using ethtool

I have a linux server with 10G fibre nics: xyz@xyz48:~$ sudo ethtool p1p1 Settings for p1p1: Supported ports: [ FIBRE ] Supported link modes: 10000baseT/Full Supported pause frame use: ...
0
votes
1answer
48 views

Is it safe and efficient to install HHVM on top Apache server with nginx as reversed proxy?

I've been trying to optimize my VPS for WordPress performance, and today, I decided to take it to a new level: I'm thinking about installing HHVM. Server status: My server runs Apache, and I have ...
3
votes
3answers
688 views

How to find virtualization performance bottlenecks?

We have recently started moving our C++ build server(s) from real machines into VMs. (MS Hyper-V) We have some performance issues that I've currently no idea how to address. We have: Test-Box - ...
0
votes
1answer
59 views

How to benchmark a whole storage infrastructure

I'm a 100% sure that I'm not the first one to consider benchmarking a whole infrastructure, but yet I haven't found any relevant information on how to face this challenge. As I guess we all know what ...
2
votes
3answers
1k views

Can tail slow down log writing speed on Linux (ext3)?

I'm wondering if tailf can generate blocking I/O which will slow down server responsiveness due to logging. For ex. assuming the following setup: Debian 5.1 linux server (foo) which is managed via ...
4
votes
1answer
56 views

Multiple websites on multiple servers - seperate mysql or not

I currently have 2 Debain boxes (VPS - 4Gb memory) and am hosting a variety of websites of different importance, some ore production sites, others are demo/staging/test sites. Approximately 15-20 ...
6
votes
2answers
113 views

Calling sync/fsync slows IO after 30 minutes uptime

After 30 minutes of uptime using Ubuntu 14.04 with an ext4 hybrid SSD I see many processes blocking IO using iotop. The root cause of this slowdown has been traced back to the Unix system call sync. ...
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0answers
16 views

Tuning and configuring Django Application with Apache & Mod Wsgi

We are running Django Application using Apache+mod-wsgi. application is taking too long to load. even a single list view page load takes 6-15 seconds. Can you suggest improvements? Provided are my ...
2
votes
1answer
884 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 ...
9
votes
4answers
2k views

Methodologies for performance-testing a WAN link

We have a pair of new diversely-routed 1Gbps Ethernet links between locations about 200 miles apart. The 'client' is a new reasonably-powerful machine (HP DL380 G6, dual E56xx Xeons, 48GB DDR3, R1 ...
6
votes
3answers
706 views

Is there a Unix / Linux command to count lines per second from stdin?

I am trying to count the number of SQL queries per second from a log file and I want to do it in real time by pipeing stdout from grep into some command. ( I am doing some performance testing ) I ...
0
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0answers
9 views

Ubuntu Server 14.04 in VirtualBox: disk performance drops with more than 1 CPU [migrated]

I'm running VirtualBox 4.3.18 on OSX 10.9.5 . I install Ubuntu Server 14.04 64bit and performed this basic disk write test: dd if=/dev/zero of=bigfile bs=1024 count=5000000 The result with 14.04 / ...
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0answers
38 views

nginx load balance not increasing request per minute

I have a flask app deployed on a gunicorn server and another server with nginx as reverse proxy. The issue is when I add one or more servers running gunicorn and use nginx to load balance, the ...
0
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0answers
58 views

Unexplicable extreme slowness on Dell PowerEdge R320, fixed only by cold reboot

At this customer's site, there are two new Dell PowerEdge R320 servers with the following configuration: A single 6-core CPU 16 GB of RAM 2x500 GB SATA disks in a RAID 1 array The O.S. is Windows ...
0
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1answer
35 views

Negative effects of setting nginx workers too high

I've seen numerous posts advising how to set nginx's worker_processes, but very few detailing what happens when this is set too high. I'm about to run some benchmarks, but I'd appreciate advice on ...
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votes
1answer
36 views

Amazon G2 not giving a much better computing performance than my laptop CPU [closed]

I have a Java console application that performs Reed-Solomon error correction on large volumes of data (~700 MB at a time), just to test performance. The application is multithreaded, I can see it ...
0
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1answer
34 views

Squid proxy performing extremely slow and sometimes doesn't work at all

I recently installed Squid on my desktop machine for testing purposes. I didn't edit the config whatsoever, and just pointed firefox at the proxy to see if it was working. Pages take an insanely long ...
0
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0answers
42 views

Why does chrome show a very long 'blocking' time (sometimes) when loading static files from Jetty 9

I'm seeing some strange behavior from Chrome when loading web resources from a Jetty 9.2.3 instance I'm setting up. In particular, I see some requests returning quickly, while others take a very long ...
3
votes
0answers
59 views

Odd performance fluctation with php-fpm and nginx

I'm running a load test against a web service. It's a php application running on php-fpm and nginx, with fastcgi. There is a MySQL backend being used for small reads only. Invariably, I'm seeing a ...
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votes
1answer
34 views

How to check my site speed? [closed]

im the developer and in charge of a company's Wordpress based site our site started to run a lot slower recently and i am trying to figure it out for two weeks now! My main problem is that every ...
0
votes
2answers
283 views

Install Winsat on server 2012? Windows System Assesment Tool

I use winsat disk to see my disk read / write speed windows 8 and it works great: cmd : winsat disk -drive c Can this be used on windows server 2012?
1
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3answers
3k views

How much performance is gained from setting NtfsDisable8dot3NameCreation = 1?

You can tune NTFS with different parameters in the registry and an TechNet articles states that you increase file performance by setting NtfsDisable8dot3NameCreation to 1 in the registry. In real ...
7
votes
3answers
2k views

Apache on Win32: Slow Transfers of single, static files in HTTP, fast in HTTPS

I have a weird problem with Apache 2.2.15 on Windows 2000 Server SP4. Basically, I am trying to serve larger static files, images, videos etc. The download seems to be capped at around 550kB/s even ...