Bypass Max – The BIOS Optimization Guide

Bypass Max - The BIOS Optimization Guide

Bypass Max

Common Options : Auto, 0X to 7X in 1X increments

 

Quick Review

The Bypass Max BIOS feature determines how many times the oldest entry in the Dependence Chain Queue (DCQ) can be bypassed by the arbiter. Once this limit is reached, the arbiter is overriden and the oldest entry serviced instead.

When set to 0X, the arbiter is not allowed to bypass the oldest entry in the DCQ.

When set to 1X, the arbiter is allowed to bypass the oldest entry in the DCQ once.

When set to 2X and higher values, the arbiter is allowed to bypass the oldest entry in the DCQ in increasing number of times.

The Auto option, if available, usually sets the bypass limit to the maximum – 7X.

A high bypass limit will give the arbiter more flexibility in scheduling the DCQ entries so that processor can better process instructions in dependence chains. Therefore, it is recommended that you set this BIOS feature to the maximum value of 7X, which would give the DCQ arbiter maximum flexibility in scheduling the entries.

 

Details

To ensure coherency of data in a multi-core processor, the processor uses a Dependence Chain Queue (DCQ) to check for dependence chains between instructions and process them accordingly. The arbiter which controls the Dependence Chain Queue can rearrange the entries to optimize their processing. This is where the Bypass Max BIOS feature comes in.

The Bypass Max BIOS feature determines how many times the oldest entry in the Dependence Chain Queue (DCQ) can be bypassed by the arbiter. Once this limit is reached, the arbiter is overriden and the oldest entry serviced instead.

When set to 0X, the arbiter is not allowed to bypass the oldest entry in the DCQ.

When set to 1X, the arbiter is allowed to bypass the oldest entry in the DCQ once.

When set to 2X and higher values, the arbiter is allowed to bypass the oldest entry in the DCQ in increasing number of times.

The Auto option, if available, usually sets the bypass limit to the maximum – 7X.

A high bypass limit will give the arbiter more flexibility in scheduling the DCQ entries so that processor can better process instructions in dependence chains. Therefore, it is recommended that you set this BIOS feature to the maximum value of 7X, which would give the DCQ arbiter maximum flexibility in scheduling the entries.

 

Support Tech ARP!

If you like our work, you can help support out work by visiting our sponsors, participate in the Tech ARP Forums, or even donate to our fund. Any help you can render is greatly appreciated!

Comments

comments

About The Author

Related posts

1 Comment

  1. Pingback: Daily Roundup: 2016-02-08 - Bjorn3D.com

Leave a Reply

%d bloggers like this: