#performance-tuning

Answer: What are some TCP tuning tips for a service hit by iPhone clients on mobile networks like 3G? #answer #solution #computers

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 bringing the users online to interact with each other.

I would like to tune the TCP implementation for the…

Answer: What are the implications of the SHOWPLAN permission on SQL Server 2005? #fix #answer #development

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 that doesn’t concern me with this user.

Are there any other issues to be aware of? From what I see it doesn’t seem like it…

Solution: what does locked % in mongostat mean? #fix #dev #answer

what does locked % in mongostat mean?

When running mongostat to look at our mongo database, I’ll frequently see the locked % number jump up, sometimes as high as 80%. Here’s a few example rows:

insert query update delete getmore command flushes mapped vsize res faults locked % idx miss % qr|qw ar|aw netIn netOut conn time 0 10 7 0 0 17 0 2.27g 5g 1.63g 0 0.1 0 0|0 0|0 22k 7k 83 15:46:10 0 21 7 1…

Fix: NetBackup Multiplexing for Oracle RMAN Backups #it #answer #programming

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 NetBackup, there is the concept of Multiplexing which is the combining of data from a number of backup clients simultaneously in order to feed modern high…

Resolved: Building a 1,000M row MySQL table #fix #development #it

Building a 1,000M row MySQL table

This question is reposted from Stack Overflow based on a suggestion in the comments, apologies for the duplication.

Questions

Question 1: as the size of the database table gets larger how can I tune MySQL to increase the speed of the LOAD DATA INFILE call?

Question 2: would using a cluster of computers to load different csv files, improve the performance or kill…

Fixed: CPU0 is swamped with eth1 interrupts #solution #development #answer

CPU0 is swamped with eth1 interrupts

I’ve got an Ubuntu VM, running inside Ubuntu-based Xen XCP. It hosts a custom FCGI-based HTTP service, behind nginx.

Under load from ab the first CPU core is saturated, and the rest is under-loaded.

In /proc/interrupts I see that CPU0 serves an order of magnitude more interrupts than any other core. Most of them come from eth1.

Is there anything I can do to…

Solution: Faster IMAP searching for Courier IMAP server on Linux #fix #computers #answer

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 improvements.

Access performance is already quite good on fairly large accounts, but search is slow. Is there some kind of tool / add-on that can…

Fixed: What are your tricks for optimizing your Subversion configuration? #fix #solution #dev

What are your tricks for optimizing your Subversion configuration?

For a Linux or Windows system, what tricks do you do to optimize your Subversion server?

The following are my current tricks for a Linux system serving over Apache with HTTPS and backed by Active Directory using LDAP authentication.

Enabling KeepAlive on Apache

Disable SVNPathAuthz

Increase LDAP Cache

Using the FSFS storage…