Performance tuning is the process of modifying a system to improve its efficiency. This is also known as optimizing.

learn more… | top users | synonyms

1
vote
2answers
125 views

Simple queries occasionally running very slowly

I have some very simple queries that occasionally run very slowly. The table viewed_sites has about 10 - 20 rows. Running EXPLAIN ANALYZE always gives a runtime of less than 3 milliseconds. When ...
1
vote
1answer
2k views

AIX network parameters to close TCP sockets of unplugged devices

We have an AIX box, running what we call in banking "ATM Switch" not the ATM networking switch, but the bank ATM driver. where we have some ATM machines connected to two server processes. The problem ...
0
votes
3answers
4k views

Oracle tuning optimizer index cost adj and optimizer index caching

What is the correct way to set the optimizer index cost adj parameter for Oracle. As a developer I have observed huge performance improvements as this parameter is lowered. Common queries are ...
2
votes
2answers
1k views

SQL Server 2005 standard filegroups / files for performance on SAN

I submitted this to stack overflow (here) but realised it should really be on serverfault. so apologies for the incorrect and duplicate posting: Ok so I've just been on a SQL Server course and we ...
0
votes
2answers
1k views

Webalizer causing high CPU load

We use webalizer to generate reports on our Apache access logs - it is useful in conjunction with Google Analytics. The problem is that webalizer uses ALOT of CPU when running. If I run top I can see ...
0
votes
1answer
565 views

Webserver: Performance impact when storing session files on /dev/shm

I have a website runing on a typical setup: Linux, Apache, PHP, MySQL. However, what's not typical about it, is that it's getting tons of traffic (400,000+ visits a day) and so, efficiency is becoming ...
2
votes
2answers
638 views

perf tuning for ESX vmfs3 on RAID

looking for recommendations on ESX4 OS - VMFS version3: RAID-5 : matching the stripe size with VMFS block size? (64K, 128K etc) RAID controller options: "adaptive read ahead, write-back" on PERC 6i ...
0
votes
2answers
378 views

DB2 insert performance - How to measure

[From stackoverflow] Im trying to find a way to speedup my inserts to a DB2 9.7.1 (ubuntu linux) Im watching vmstat and trying to gather some statistics via the db2 get snapshot commands but im not ...
1
vote
2answers
329 views

How do I objectively measure an application's load on a server

All, I'm not even sure where to begin looking for resources to answer my question, and I realize that speculation about this kind of thing is highly subjective. I need help determining what class of ...
2
votes
1answer
213 views

Outbound HTTP performance tuning recommendations

I'll detail my exact setup below, but general recommendations for a better web-browsing experience will be useful. A nice checklist of things to try would be great! I have 600 users on a single site ...
7
votes
2answers
1k views

What are the implications of the SHOWPLAN permission on SQL Server 2005?

A user wants the SHOWPLAN permission in order to use Execution Plans to tune a query. What are the implications of this permission. Is it safe to grant a user? I've seen the security note here, and ...
1
vote
4answers
559 views

Optimizing MySQL server

I need help in optimizing my my.cnf configuration file. I have two servers connected directly through LAN network (1 GBit/s). The first server is an Apache web server and the second one is a MySQL ...
2
votes
3answers
1k views

How to optimize iptables for high DNS traffic?

How to optimize iptables for high DNS traffic? I have a dedicated linux server acting as bridged firewall using iptables. Recently behind firewall was deployed DNS server with high load and firewall ...
6
votes
1answer
1k views

What are some TCP tuning tips for a service hit by iPhone clients on mobile networks like 3G?

I am a developer that has the good+bad situation of designing a network service that will be hit very hard by iPhone clients. The iPhone app has over 10MM downloads in the past year and now I'm ...
1
vote
1answer
466 views

postgresql - cache preferences per table/db

i'm curious if there is any way to hint postgresql which data should be more likely cached in memory. in my scenario the server would be handling mostly read traffic, whole data-set is much larger ...
1
vote
5answers
202 views

Network Monitoring and Filtering [closed]

As the IT administrator for my company I have been tasked with deciding what traffic to filter, shape, and othewise monitor on our network. What protocols, applications, and other network traffic do ...
0
votes
1answer
1k views

How to use oprofile to find the bottle-neck of our web server?

Updated: ================================================================ I finally found the reason with oprofile. It was because the routing cache of Symfony. We have lots of pages with different ...
1
vote
2answers
370 views

Is there any way to exclude specific files / directories from SuperFetch?

Overall, I love the SuperFetch feature in Vista and believe it results in hugely noticeable gains in the launch time and overall "snappiness" of the system. However, sometimes it apparently gets ...
1
vote
2answers
3k views

Interpretation of non-zero vmstat “bi/bo” values

What are useful rule-of-thumbs with regard to interpreting non-zero vmstat "bi/bo" values? When are the values "okay" and when are they an indication of that the system is under heavy stress? The ...
1
vote
2answers
543 views

How well does Windows 7 Handle High Bandwidth-Delay Product Networks

As WAN bandwidths increase default network settings in older operating systems are less and less able to efficiently use the network. A description of the problem with high bandwidth-delay product ...
3
votes
3answers
262 views

How to profile for HDD usage pattern?

I'm considering upgrading the storage system for some of my servers, and all the guides and manuals advise to consider the storage usage patterns of your app before deciding on a (RAID? SSD? iSCSI? ...
3
votes
4answers
963 views

How can I make this setup faster?

Hey StackOverlow Community, I currently am using some software that stores a bunch of XML files. All the files are under 25k bytes. The makers of the software state the performance is based on ...
1
vote
3answers
93 views

SQL Server Tuning Resources

I want to learn more about tuning SQL Server instances (2005/2008), does anyone have any good resources they can point me at? Dave NB: I'm talking about the hardware/instance configuration side of ...
1
vote
1answer
753 views

Virtual server freeze (apache ?)

I rent a small virtual server at 1und1.de. (Link, but German only) (2GB RAM dynamic, 512MB at least, 20 GB HDD) I choose to run a Ubuntu 8.04 LTS as operating system (64 Bit). I installed apache2 + ...
2
votes
3answers
4k views

How can I improve NFS performance on a gigabit LAN?

I have a Solaris 10 server with a Mac OS X clients on a gigabit LAN. The Solaris server exports a RAID-Z backed NFS share and all the clients connect to it. However, transferring files is slower ...
6
votes
4answers
4k views

Configuring NTFS file system for performance

We have an application that is planning to store around 1.1TB of XML files which average 8.5kb in size. These represent a rolling 18 months of data, with around 200,000 new files being created every ...
5
votes
2answers
4k views

Faster IMAP searching for Courier IMAP server on Linux

I am looking for tips on improving IMAP search performance using Courier IMAP. The current version is 4.2.1. Unlike in the question "Fast search for IMAP?", I'm specifically looking for server side ...
3
votes
3answers
891 views

What should I set the initial MySQL Values in My.cnf to for Performance?

I am just setting up my new Linux Ubuntu 8.04 LTS server now, and getting ready for launch. My application is a PHP built application using the Zend Framework, and there is a MySQL heavy site (as are ...
1
vote
1answer
2k views

How to change the SWAP file disk in Mac OS X?

I have moved my system on andexternal Raid 1 enclosure attachet to my iMac through Firewire 800 (the best an iMac can do ;-( ) ... I'd like to move the swap on the internal disk in order to increase ...
-3
votes
2answers
728 views
7
votes
3answers
3k views

NetBackup Multiplexing for Oracle RMAN Backups

My question is... what multiplexing factor in NetBackup is recommended / do you use for Oracle RMAN backups over 1Gb/s management network to LTO3? JB Background: With enterprise backup tools like ...
2
votes
1answer
126 views

What resources on OpenVMS Performance Management do you recommend?

I'm looking for details about how to measure OpenVMS performance, such as what all of the different reported statistics mean and how to adjust for them. In particular, I'm currently investigating ...
1
vote
5answers
683 views

Trouble shooting wireless signal performance

I just performed a wireless network scan and my primary wireless route broadcasts a consist 70 DBm signal. I added a range extender that increases or decreases the signal 65 DB (Not sure how the DB m ...
0
votes
4answers
270 views

Exchange 2003 I/O Troubles

We have some internal processes that send email to our Exchange 2003 system (on Win2K3 R2 32bit). Recently they have been intermittently failing with various errors -- boiled down they report ...