ARRI Projection HDTV 4.3 Fine-tuningALICE, Configuration, Multi Threading, Memory Footprint

4.3.

4.3 Fine-tuning ALICE

Memory Footprint Multi Threading

Configuration

The amount of memory ALICE consumes depends on the maximum image size to be processed, and the maximum size of its internal image cache.

The image cache limit can be influenced by the environment variable ALICE_MEM_FRACTION.

Its value is the percentage of the memory marked available to the application by the operating system. Default is 0.25, meaning that a quarter of the memory is the upper limit of the image cache. Note that this is the image cache only, not the total memory footprint of the application. The environment variable can be set in

‘c:\cshell\login.csh‘.

Besides running parallel to image loading and recording, the image processing can operate multi-threaded to make optimal use of the dual CPU system.

When running ALICE at the same time as recording on the same host computer, multi-threading can be switched off by setting ALIP_THREADS to 0.

This affects both ALICE as well as image processing for recording. Setting ALIP_THREADS to 1 turns on multi- threading, while setting it to “auto” causes the multi threading to be turned on, but to be disabled it temporarily if both ALICE and aldaemon are running at the same time, to allow interactive working with ALICE while computing data-intensive recordings. The auto setting is also the default if the environment variable is not set. The environment variable can be set in

‘c:\cshell\login.csh‘.

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