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

learn more… | top users | synonyms (2)

3
votes
6answers
290 views

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

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 ...
-1
votes
0answers
20 views

Two small VPSs or one bigger VPS? [duplicate]

I have a relatively busy WordPress site (http://ndsmcobserver.com). I'm currently on Linode 2GB plan, but performance is pretty sluggish, especially when performing searches and working every night ...
3
votes
1answer
30 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
55 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
12 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
12 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
65 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
35 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 ...
12
votes
4answers
2k 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
28 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
27 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
98 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
31 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
50 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
0answers
36 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
44 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
22 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
61 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
40 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
58 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
11 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
35 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
62 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
20 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
18 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
78 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
18 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
24 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
90 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
22 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
52 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
22 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
38 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
8 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
20 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
2answers
40 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
27 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
28 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
185 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
60 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 ...
4
votes
2answers
108 views

Does LXC container performance depends of host load?

I am wondering if LXC could offer a full isolated benchmarking environment. Let's say we have 2 identical machines, with the same fresh Linux and without network connection. First machine has a load ...
1
vote
2answers
99 views

How to improve a Java build server's performance?

We are setting up a new server for integration build. The original integration server can finish the "mvn install" in 3 minutes in a Linux box. Now by moving to a Windows 2012 server on VM, it's down ...
0
votes
0answers
72 views

Poor network performance when fileshare with CentOS on HyperV

I own Fujitsu Siemens server (TX100 I guess – I am not able to check this as I manage it remotely). I have got Windows 2008 Standard R2 sp1 installed. On this server I run Hyper-V and in it I have ...
1
vote
3answers
154 views

How many IOPS do I need? My workload bottleneck is storage

How can I know how many IOPS I need my storage to deliver for my overloaded Linux server? I have a server and I know it has storage as its bottleneck. I would like the bottleneck not to be storage, ...
1
vote
0answers
58 views

SSD+MDRAID+LVM+KVM results in lower performance than expected

We use kvm for virtualization, the disk images are stored as logical volumes. The logical volumes are stored on a bunch of software-RAID1 (mdadm) arrays composed of Intel DCS3500 SSDs (each array is a ...
1
vote
0answers
44 views

Postfix performance and how to increase my throughput?

What I've read so far: Postfix Tunning Postfix Bottle Neck Analisys The Book of Postfix (chapter 22) I have similar specs to this guy but I'm only able to send about ~1300 emails/hour What I've ...
1
vote
1answer
57 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++ ...
0
votes
1answer
172 views

How to troubleshoot slow performance on AWS EC2/RDS?

We recently moved our web servers from some 10 year old boxes to AWS EC2. Usage of the site is currently higher now (it's our busy season) and the site has become much slower, which is unexpected ...
1
vote
2answers
51 views

Splitting web project across multiple partitions on Linux (SSD, HDD and RAM Disk)

I've got a web project that pretty much consists of three parts: Code, Assets and Cache. I'm thinking of splitting it through multiple drives - Put my whole Code into SSD partition, Assets onto big ...