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

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2
votes
2answers
185 views

Is there anything I can do to decrease waiting time for my static http requests (in chrome's network panel)?

I am running amazon aws ec2 micro instance on Ubuntu 14.04 with apache 2.4.9. The reason for having this instance is just to test and to solve some bugs before rolling up the project. Currently there ...
2
votes
2answers
110 views

Azure IO performance

We have a number of Windows Server virtual machines that we use for .NET and Java development and QA. I find Azure attractive for the obvious reasons but mainly for the opportunity to reduce ...
0
votes
2answers
96 views

Debugging slow transfer rate from server

I'm trying to explain this as simple but documented as possible. This is not exclusive to this server or my current ISP. I've seen the same exact issue over the years while being with different ISPs ...
8
votes
2answers
263 views

Do unused application pools in IIS affect performance?

Due to a major update in our architecture, we now have a few unused application pools under IIS (there are no web sites mapped to them). I understand how it can a good idea to remove them just to ...
0
votes
1answer
57 views

Ignore utm_* values with varnish?

Can I 'ignore' query string variables before pulling matching objects from the cache, but not actually remove them from the URL to the end-user? For example, all the marketing utm_source, ...
1
vote
2answers
217 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 ...
1
vote
0answers
43 views

IRQ not handled by all CPUs

I have a problem about balancing irq. I took irq numbers from /etc/interrupts and assigned each irq to each of 24 CPUs as this tutorial says for i in {143..166};do cat /proc/irq/${i}/smp_affinity; ...
0
votes
0answers
85 views

Trying to find bottleneck… 60k onsite visitors

I know this will be hard, but I'm willing to try the Q&A route. I have a Wordpress site that currently has 60,000 visitors on the site at once. I'm using an EC2 m3.xlarge, php/php-fpm 5.5.10, ...
3
votes
1answer
126 views

Filesystem performance degraded during RAID rebuilding

So quick question - our RAID6 array is currently rebuilding and there is a VERY noticeable filesystem performance hit (home directories are NFS mounted on the array). I'd sort of expect that, given ...
4
votes
1answer
147 views

Mail Server Storage Backend: Filesystem VS Database

I am trying to compare mail server software to decide which to use at the ISP where I work. I'm confused mainly about which storage backend is better for such use (again, at an ISP, i.e expected large ...
4
votes
6answers
367 views

When is it time to add more cores to your virtual server? [closed]

I have a Linux (RHEL 5.8) server with Java 7 and Tomcat 7. The performance is poor, and I am pretty sure it's the DB queries that are slow. We have 2 cores right now, and load average never exceeds ...
3
votes
1answer
94 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
votes
3answers
114 views

Linux: Get information/stats about storage network

I want to know as much info as possible about the SAN a linux server is connected to. What commands will give me the most comprehensive view? Simply knowing the WWN of LUNS doesn't do much for me. ...
0
votes
2answers
22 views

Distributed LAMP vs DB and Web Server same box

We have a very read heavy semantic web (RDF) application which is RHEL 5/Apache 2.2.3/Tomcat 6/Java 6 on one Server, and MySQL 5.1 on another. Apache and MySQL are backported Red Hat repo stuff, so ...
1
vote
0answers
138 views

apache performance static file

I have a fairly low-budget VPS (1GB RAM + 2 CPU's) to run a few (5 - 10) different small websites (both static and dynamic). These websites have (very) low traffic (average of 500 unique visits for ...
3
votes
2answers
108 views

Intel Xeon E7-4807 vs Intel Xeon X5690

We replaced our main line of business server with a new one. The old server had dual Xeon X5690s in it (2 generation old chip), the new server has quad Xeon E7-4807s. We expect processor performance ...
0
votes
2answers
90 views

Logging detailed network activity on Windows Server 2008

One of my clients is experiencing internet delays and outages within their small network. They've verified with their cable company that the issue is not related to any cable company outages. The ...
11
votes
4answers
3k views

Why is 1 of my 24 CPUs Pegged at 100%?

I have an HP ProLiant DL380 G7 system using 2 6-core CPUs, with Hyper-threading enabled, for a total of 24 logical CPUs (as seen by Windows). When running our application, total system CPU ...
0
votes
0answers
155 views

Optimizing disk performance on KVM VM configuration

I have a KVM host server running Ubuntu 12.04 LTS, bare bones installation with only KVM installed. The server has an 8 Core Intel(R) Xeon(R) CPU E3-1230 V2 @ 3.30GHz CPU with 32GB of RAM and SATA ...
0
votes
0answers
48 views

when and how to appropriately use /proc/sys/vm/drop_caches

You can clear page cache with /proc/sys/vm/drop_caches. Can someone provide a practical explanation of how this works, when as a sysadmin you would want to do this, how to determine if your system ...
3
votes
3answers
158 views

Can a Hyper-V machine be made slower and/or emulate a slow network connection?

I need to reproduce an issue with a client-server asynchronous communication (a bunch of JavaScript AJAX vs. an OData api), seemingly caused by some race condition in the calculations when the server ...
0
votes
0answers
6 views

Running Drupal on Amazon EC2 with optimal performance [duplicate]

I'm currently running multiple Drupal sites that have reasonably low traffic on an AWS EC2 m1.small instance. The EC2 instance is running Windows Server 2012 and IIS8. I'd like to know generally ...
1
vote
1answer
53 views

can Iowait cause significant RAM consumption increase

I have a node.js process running continuously on a linux EC2 instance, it extracts data and stores it in mysql. Some reads are also performed on the database. The process can run well during hours or ...
1
vote
1answer
177 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 ...
1
vote
1answer
126 views

upgrade/reinstall vmware vsan from beta

Being a VSAN beta tester I decided to upgrade to GA version as VMWare suggests for production sites. They say, it is not possible/supported to upgrade from beta to GA version, and I did not upgrade, ...
0
votes
0answers
78 views

Block requests based on hostname

Has anyone used this module in their Nginx setup? If yes, I would like to know about it's performance. How much would it affect the response time etc. https://github.com/flant/nginx-http-rdns The ...
0
votes
1answer
241 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 ...
2
votes
2answers
116 views

performance tuning vs understanding a memory leak?

I've read just about every blog post and serverfault answer relating to this, but have seen absolutely zero improvements to the server's CPU or Memory usage so I feel like I'm missing something. At ...
0
votes
1answer
52 views

size of extent on LVM2

in LVM1 there was a limit of 65k extends. So size of extent had to been chosen carefully between wasted space on partitions (to big extent) and maximal possible size of logical volume (too small ...
0
votes
1answer
69 views

Best way to optimize site speed for a large traffic website? [closed]

I'm currently managing a Website for a client of mine who gets about about 500-1000 visits minimum a day, and this includes Members uploading videos, photos, blog posts and other content. The site ...
0
votes
0answers
97 views

mod_pagespeed own js and css render blocking

My mod_pagespeed gives a lower score because it's own js and css are render blocking. Given that the tool is designed to speed up, not slow down, I don't think this is desired behavior by design. Has ...
0
votes
0answers
74 views

Ubuntu server router - only 50% of upload bandwidth

I've changed my internet connection to 400 mbps download and 400 mbps upload. Real speeds when computer connected directly to optical modem: 421/412 mbps for download/upload. My network structure is: ...
0
votes
2answers
81 views

How do I prevent a website on my server causing the whole server to crash

I have a server with 6GB of RAM and a 6-Core CPU. Number of websites hosted by the server is about 10, but sometimes 2 of them take 100% CPU and almost entire RAM which cause the whole server to crash ...
0
votes
0answers
34 views

How do I check disk performance of LVM drive?

I have a CentOS server with 2 hard drives configured to use LVM over RAID1. How do I benchmark my hard drive? As seen in this question, I have used the following commands: # check read performance ...
1
vote
0answers
31 views

Frequent CPU spikes on fresh install

I just reinstalled my Server (Windows Server 2008 R2) and after installing MySQL 5.6, the CPU spikes every few seconds: http://s15.postimg.org/dno7ztfjf/cpuspikes.png Even worse than the higher CPU ...
0
votes
1answer
135 views

Abnormal CPU usage during Disk Write Operations

I have a decent CentOS 6.5 dedicated host (CentOS 6.5/E3-1230 3.2Ghz Quad Core + HT/16GB/Software Raid 1 SATA II/WD2503ABYX/ext4) with the default CentOS kernel and "elevator=deadline" in grub. I/O ...
0
votes
0answers
20 views

Can the estimated time of access times for distributed keyvalue stores be below 1ms?

I'm digging through various Redis/Ceph/Elliptics benchmark to determine, whenever its theoretically possible to reach (very optimistic) request completion time below milliseconds in a non-SSD ...
0
votes
0answers
63 views

Debian mail server's Maildir folder with too many files causing disk I/O to go on high load

I have a Debian mail server running Postfix, Courier and Maildir, with disks on EXT3 filesystem. I have noticed that when I use my webmail application (Squirrelmail, in this case). It gets some kind ...
1
vote
2answers
350 views

HP Smart Array P822 w. Dual D2700 - cabling for best performance

Reading the D2600/D2700 User guide, there's a section called "Cabling examples", but none of the examples match what we intend to do. I just want to make sure that it makes sense, before we do it. ...
1
vote
0answers
50 views

IIS: how to determine most effective CPU throttling % [closed]

We have about 30-35 sites per server across 8-10 servers at a time depending on load, for a total of ~300 sites. The sites are more or less hosting slightly customized versions of the same .net web ...
0
votes
2answers
101 views

MySQL's InnoDb performance downfall

I'm trying to configure a MySQL production server using InnoDb and I can not get the performance I want out of it. I've used Percona tools to give me the following configurations: [mysql] # CLIENT # ...
0
votes
0answers
33 views

RAID6 Ubuntu rebuild - how to calculate best parameters for fastest rebuild

I am doing a resync on a RAID6 array and I am looking at some 2 days to complete. I looked here for hints on how to speed it up, but I have, instead, managed to slow it down! HW details are: 10x 4TB ...
-2
votes
2answers
51 views

Do domain registrar affect the ping time of your domain? How to optimize? [closed]

The background story: recently I switched to use cloudflare as the name-server of my domain(which use namecheap as registrar). I noticed a increase in ping time. Then, I moved another domain(with ...
0
votes
0answers
10 views

Scopserv System Load Average

Firstly, apologies for what will be a slightly less than technical explanation of the problem I am facing - I am not a SysAdmin and therefore have a somewhat limited understanding of the issue I'm ...
0
votes
0answers
71 views

AIX JFS2 I/O performance problems

I have a fresh installation of AIX 7.1. I noticed that JFS2 file system with logging enabled (log=/dev/hd8) is dramatically slower than one with log=NULL. Simple zip archive extraction takes 5 minutes ...
0
votes
3answers
77 views

Is it possible to use curl to accurately stress test a site that has lots of javascript?

I have a web site that has lots of javascript but simple html. I want to try simple stress tests with curl. Is that possible? If I just curl the site I get HTML. So making tons of curl requests won't ...
0
votes
1answer
36 views

Horizontal Scaling Alternatives To GFSv2 (slowness)

I'm having an infrastructure design problem with an application. Right now we access a lot of small files (under 10MB) from a GFSv2 2-node cluster. 90% of file access is "random reads" to this GFSv2 ...
0
votes
1answer
63 views

Performance and Microsoft Security Essentials Real Time Protection on Server 2008

Is it smart to turn off real time protection for Microsoft Security Essentials on Server 2008? Will this help with performance? I have it running a scan every night.
4
votes
2answers
651 views

VMXNET3 performance on Linux on ESX 5.0

What kind of performance can I expect from VMXNET3 adapter when running two Linux guests on the same VMware ESX private network defined between those guests? I use VMXNET3 adapter for communicating ...
0
votes
1answer
85 views

Improve Disk Performance of a Linux 2.4 Guest on KVM Host

I have a server running Linux 2.4, and I'd like to virtualize it using KVM. I can run it with a IDE controller, but my applications require more disk performance. The best existing solution is using ...