Linux Desktop Hacks

Tweak Your Kernel Without Recompiling #91

Chapter 10, Kernel

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HACK

behave for a few hours. Then set it to a low number, continue to use your

computer for desktop operation as you normally would, and see for your-

self what the difference feels like. Then pick the performance characteristics

you like best. Perhaps you’ll even be happiest with a default value of 70.

Tuning Network Performance via /proc

Here are a couple more parameters you might want to tweak, especially if

you are using a home computer hooked directly to a DSL or cable router:

# echo "0" > /proc/sys/net/ipv4/tcp_sack

# echo "0" > /proc/sys/net/ipv4/tcp_timestamps

These settings turn off some unnecessary network activity. You might not

perceive any change in performance, but it’s worth a try.

Tuning Disk Access via Your Bootloader

Each program you run under Linux will want to access the disk at some

point or another. The Linux kernel determines how to prioritize how each

program gets access to the disk, using three methods: Anticipatory Schedul-

ing, Complete Fairness Queuing, and Deadline Queuing. (Actually, the ker-

nel uses a fourth method, called

noop, but noop is not likely to be applicable

as a default method for a desktop user.)

Each method has its advantages and disadvantages. Only two of them are

likely to be appropriate for desktop performance: Anticipatory Scheduling

and Complete Fairness Queuing. Most people seem to favor ...