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

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4
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2answers
3k views

How to calculate required switch speed based on network usage?

I have a 48 100Mbit/s port HP Procurve Switch 2610 (J9088A) that can handle 13.0 million PPS (packets per second) and features wire speed switching capacity at 17.6Gbps. First off, what does that ...
1
vote
1answer
165 views

Erratic write patterns with linux md RAID1

I'm experiencing strange write performance patterns on a RAID1 array of SATA disks. My kernel is vanilla 2.6.37 and my server has 32G RAM. I'm copying a 32G file from an XFS filesystem on a SAS drive ...
2
votes
2answers
640 views

10tb file storage design question on media website

I have a fairly busy media website where MP3 audio files are uploaded by members and streamed / downloaded from 2 Windows servers which are load balanced at the moment...both servers simply mirror ...
1
vote
1answer
595 views

Poor MD3000i read performance (for one controller, but not the other)

We have an MD3000i array accessed by three separate servers (all blade servers accessing through chassis nic's). Controller 1 (both Ports 0 and 1) are linked to Server A. Servers B and C (both with ...
0
votes
2answers
642 views

scp vs netatalk, samba, and/or vsftpd with External USB drive

I set up a ubuntu server machine to share an ext2 formatted external usb drive. When attempting to copy a single 275MB files from said device through netatalk, I get estimated download rates at around ...
1
vote
1answer
88 views

Url Redirections using .htaccess

I would like to add 1500 url redirections using .htaccess on a apache server. Is it a bad idea ? will it decrease the performances significantly? Thanks
2
votes
2answers
6k views

HP SmartArray P400 has slow read and write speed

I have desktop in which I installed HP SmartArray P400 controller with two HP DF0146B8052 hard drives. I made RAID0 logical volume from them, but I am getting 20MB/s write speed and ~140-120MB/s read ...
1
vote
3answers
355 views

Config MySQL to maximum speed and memory

I have a server, 8 cores, 12 GB RAM. This server is only used to run MySQL. So, help me config /etc/my.cnf to maximum speed, memory for MySQL.
1
vote
1answer
331 views

Running game server and webserver on EC2

Hey guys, I have a webhost, and an EC2 server (to run a game server on). The problem is that I want to access/modify the EC2's files with php admin programs. I looked into a lot of options to just ...
0
votes
2answers
2k views

IBM AIX Vs Intel Performance

Can anyone help me in comparing the performance of an IBM AIX 570 Power 5 8 Cores computer with the latest Intel 6 Cores. Thanks
7
votes
1answer
503 views

sys.dm_exec_query_stats interaction with recompilation

We use sys.dm_exec_query_stats to track down slow queries and queries that are IO offenders. This works great, we get a lot of very insightful stats. It is clear this is not as accurate as running a ...
2
votes
2answers
310 views

POP3 traffic stalls between small bursts

What follows is a description of the strangest network problem I have encountered. The story I am working with a client that reported being unable to check their email, starting this morning. Two ...
0
votes
2answers
914 views

Download Speed is 0.12 Mbps when tested with servers in U.S, but it is 0.76 Mbps when tested with local servers, normal?

Feeling that my ISP is cheating my money ( My subscription package is 1 Mbps), I did a speed test on my internet connection using www.speedtest.net. I tried to test the connection speed on two ...
3
votes
1answer
846 views

Measuring Disk IO programmatically

I want to measure some numbers related to disk io in a given timespan, programmatically. This means I don't want to spawn a process like iostat to get my numbers, by prefer to read something from proc ...
1
vote
1answer
1k views

linux quota reporting performance

I have a system with over 10,000,000 files where I want to track the disk usage of a couple of users (these users own the millions of files). Based on the following Q&A http://stackoverflow.com/...
0
votes
3answers
195 views

finding the bottleneck

I have a process running that is opening TIF files. Each TIF file is just one regular page and they are maybe 100 kB each. Every time he opens a TIF file it tries to read a barcode in a specific area ...
1
vote
1answer
961 views

How to prevent the slow first load startup for a website?

I'm sure you've noticed that for many servers, the website loading time is quite long if you're the first visitor for a couple of hours. Do you have any idea why this is the case (is it just server ...
7
votes
5answers
7k views

Freebsd or Linux? as BGP router over 100mbps

I am building a server to act as a BGP border router for my 100mbps uplink in ISP. I needs these feature: 1) Dual stack BGP peering/routing (at least 100Mbps, maybe more). 2) Potential full internet ...
0
votes
2answers
437 views

Linux: CPU usage artificially capped somehow?

This is the CPU usage graph of a server: It seems that the CPU usage reached a hard limit at 24. This is a 32-core server so it should be able to go beyond 24 with ease. But that's not the case. ...
6
votes
1answer
2k views

IPSec software that can use multiple CPU cores

Can anyone recommend a good IPSec software that can use multiple CPU cores to achieve performance ~2Gbps on Linux dual-CPU quad-core E5620 Xeon setup (total 16HT cores)? I have tried OpenSwan and ...
0
votes
4answers
1k views

MySQL server CPU usage shot up for no apparent reason. Any idea why?

I have a server dedicated to MySQL. In the middle of the night its CPU usage just shot up for no apparent reason. Here're the graphs: As you can see CPU usage just shot up at Fri 3:30am. Most of ...
0
votes
1answer
146 views

MySQL's Query Optimizer's take on disk access time

I don't have a ton of background with MySQL, and I was wondering of anyone can give me some insight into MySQL's query optimizer and the impact on the cost of disk accesses in determining a query plan ...
1
vote
3answers
285 views

Experience with Intel X25-M 160GB and Oracle

We're considering building an Oracle database with 12 Intel X25-M G2 160GB drives in software RAID10. It'd be running Linux. Database gets some very heavy write activity during the early morning data ...
0
votes
5answers
1k views

My dedicated server keeps getting very slow that it fails to load the application

I have an application running on Windows Server 2008, running IIS 7.5, SQL Server 2008, 4GB RAM from brinkster. The problem is, every couple of days I get the same 10,000 calls that the system is ...
7
votes
2answers
4k views

pg_restore taking much longer than pg_dump

I am regularly saving and later restoring a smallish PostgreSQL database, which is used for testing. Its data is updated regularly as a result of tests, then a new dump must be made, and the dumps are ...
0
votes
3answers
177 views

Network issues - Windows Server 2003

I am having network issues on my Windows Server 2003. I am running this test: I am pinging my server from remote location constantly (ping -t) I am pinging a stable web site from my server ...
0
votes
1answer
107 views

Need to improve performance on a server

Since converting online backup to an in-house backup (ArcServe) performance on this server has degraded considerably. Does anybody have recommendations on tuning for performance?
1
vote
3answers
745 views

Any open source software for measuring & monitoring MySQL performance?

I'm working on improving the performance of a MySQL server. I'm looking for something to measure & monitor the performance of MySQL (as query per second) over time so that I can measure any ...
1
vote
2answers
339 views

RAM Size vs Speed

I have a server with 4 DDR2 RAM slots. I just bought 2x2GB 800MHz sticks for it, for a total of 4GB RAM. I also have 2x512MB 677MHz sticks left over. Is it better to use the 2x2GB sticks at 800MHz ...
0
votes
1answer
2k views

Apache mpm-itk Performance

I manage a bunch of VPSs with memory ranging from 1GB to 8GB. Most of these websites are Joomla websites, and the servers must support multiple sites/users/S-FTP. I use mpm-itk almost exclusively (...
1
vote
0answers
151 views

SAS disk performance drops a while after reboot on cent 5.5 boxes

So we have some workstations with identical hardware. The Fedora14 box has a couple weeks uptime and still get good performance. hdparm -tT /dev/sda /dev/sda: Timing cached reads: 21766 MB in 2....
-1
votes
2answers
129 views

Hard Disk Speed for Virt Laptop [closed]

If I want to run a few dev VMs on a laptop, how fast do my drives realistically need to be? I do not expect lightning fast performance, but the last time I tried this on a Lenovo Thinkpad T400, ...
2
votes
1answer
753 views

Very long IO wait times

Following scenario has happened twice with different RAID controllers. One was LSI MegaRAID running RAID5, the second was HP Smart Array E200i running RAID1. At first server works smoothly for few ...
0
votes
1answer
202 views

optimize mysql queries perfomance and speed

i need some help in some mysql queries i'm trying to improve it's performance and speed i'm trying to figure out how to do that using mysql syntax . here is an snippet of a query function i use ...
2
votes
1answer
176 views

SQL Server 2008 Partitioned Table and Parallelism

My company is moving to SQL Server 2008 R2. We have a table with tons of archive data. Majority of the queries that uses this table employs DateTime value in the where statement. For example: ...
2
votes
1answer
335 views

DNS lookup performance penalty with exotic TLDs?

When tuning a web site/service for performance, is there a downside to using a less common top-level domain (e.g. 'nu', 'tv', 'io') for your hostnames? My concern is that if you're using a TLD ...
2
votes
1answer
167 views

How to track down an io-bound botleneck

I'm currently working on optimization of a web server, however I'm quite stuck at one particular problem. I'm using jmeter to simulate simulate load. jmeter is configured as follows: 400 threads ...
1
vote
3answers
471 views

VOIP and internet connection speeds [cable vs. fiber]

Our office is migrating to IP telephony. We have less than 10 employees that will be using the phones. We currently have cable internet, and they just bumped the speeds: There is a data center ...
1
vote
2answers
4k views

How to test disk latency on Linux?

Made an upgrade of RAID firmware and latency as it seems have increased. Could you please advise on the most accurate way to examine disk read and write latencies?
1
vote
1answer
423 views

BIND and DHCPd performance

I've a little question. Is there any usual performance matrice on DHCPd and BIND services? I mean, can I scale my servers depending on my clients numbers and then how? Can I found somewhere a ...
81
votes
13answers
24k 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
2answers
698 views

How do large blobs affect SQL delete performance, and how can I mitigate the impact?

I'm currently experiencing a strange issue that my understanding of SQL Server doesn't quite mesh with. We use SQL as our file storage for our internal storage service, and our database has about half ...
1
vote
1answer
2k views

How do I see if my disk cache is disabled on Linux?

I have an ubuntu linux virtual machine here and I think there is no disk cache. For example this is the output from free -m: total used free shared buffers ...
1
vote
2answers
1k views

Samba PDC share slow with LDAP backend

The scenario I have a SUSE SLES 11.1 SP1 machine as Samba master PDC with LDAP backend. In one share there are Database files for a Client-Server application. I log XP and Windows 7 machines to the ...
2
votes
1answer
113 views

Is it Good to place Windows Server paging files on seperate fast storage?

How much of an impact does the performance of the storage system hosting the paging files of windows machines (I guess both physical or virtual instances like VMWare / KVM / Xen / Whatever)?
-1
votes
1answer
95 views

Virtual desktops on Windows Server 2008 [closed]

I've been asked to setup a Windows server, and also help purchase it. I am in academia, so educational discounts apply. However, we do not have an unlimited budget; it's around $6k. I'm looking for ...
0
votes
1answer
317 views

Simple MySQL query locking up until database restart

I have a very simple query that runs in 216ms on my development machine but was taking more than 45 seconds on my production server, that is, until I restarted MySQL there: UPDATE `forum_categories` ...
0
votes
1answer
301 views

A Most Puzzling MySQL Problem: Queries Sporadically Slow

This is the most puzzling MySQL problem that I've encountered in my career as an administrator. Can anyone with MySQL mastery help me a bit on this?: Right now, I run an application that queries my ...
1
vote
2answers
1k views

Terrible Performance with SATA Drives on Dell PowerEdge, steps to troubleshoot?

I had asked this question earlier and the question went missing so here it is again. Bought a DELL Poweredge 2950 to use as in-house QA Server. Disk performance is beyond terrible, 1000-4000 ms ...
2
votes
3answers
2k views

Poor software raid10 read performance on Linux

I've recently set up new Linux based file server. The distribution I'm using is Ubuntu 10.10. I've created two software raid devices as follows: mc@vmr:~$ cat /proc/mdstat Personalities : [linear] [...