Memory allocation

Controlling Omniscope RAM memory usage

By default, Omniscope limits itself to 75% of physical RAM memory. This value was chosen to ensure there is sufficient free memory in the system to perform other tasks and run other applications without degraded system performance.

The 32-bit version of Omniscope applies a further cap of 1100MB to this value, to resolve a limitation of 32-bit Windows where larger values cause Omniscope not to start due to lack of contiguous memory. This cap is set to cover 99% of 32-bit Windows PCs, but it could safely be set higher on many 32-bit PCs. You can control how Omniscope manages RAM memory on both 64-bit and 32-bit installations by changing this and other settings.

Increasing RAM accessible by Omniscope

When you start Omniscope, the application launcher determines how much memory it should allow Omniscope to use.  In very rare cases the setting may not be correct and causes the application not to start.  More commonly, Omniscope may start with less memory than possible, which you may wish to change change the upper limits if your data sets will be pushing the boundaries of accessible RAM on your machine.

Warnings and disclaimers

This is for advanced use only, as incorrect settings may stop your Omniscope installation from working.

With 32-bit Omniscope, if you specify too high a setting, Omniscope will not start. If this happens, reduce the value (perhaps in 100MB steps) until Omniscope starts successfully. You may be able to go as high as 1900MB, but it is unlikely you can go any further without using 64-bit Omniscope on a 64-bit operating system.

With both 32-bit and 64-bit Omniscope, you should never specify more than the installed physical memory, and should ideally leave some headroom for the operating system and other applications otherwise performance will be degraded. Vista is particularly memory hungry, and should always be left at least 2 GB of memory when allocating allowable memory to Omniscope.

Instructions

In the Omniscope Program Folder (typically found in Windows at C:\Program Files\Visokio Omniscope for 32 bit, or C:\Program Files (x86)\Visokio Omniscope on installations which are 64-bit) there is a file called installconfig.properties.

You will need administrative permissions to edit this file.  If using Vista or another Windows OS with user account control, you will find it easier if you copy this file to your desktop before editing it, then copy it back after editing.

Open this file in Notepad (it should look similar to the example below) and look for the line starting #MAX_MEMORY_MB= (highlighted below). By default this line is commented out with a #.  Remove the # in front (and leave no spaces at the beginning of the line), and enter the value in MB (e.g. 3500 for approximately 3.5GB) at the end of the line. Save the file with this change. 

To revert back to the default 75% max memory allocation, replace the # sign at the start of the line.

Examples

On a 32-bit PC with 2GB memory, we recommend pushing the limit up to 1750MB, providing Omniscope will still start. On some PCs this will give a significant boost to the capability of Omniscope. On a 64-bit PC with 12GB memory and a 64-bit Omniscope installation, we recommend going as high as 10GB (10000). This will give a moderate boost.

Example to set the limit to 1300MB

Setting the memory for the Scheduler / Windows service

Edit your wrapper.conf file in the "service" folder of the Omniscope installation.  Change the line below as follows; in this case we are setting the limit to 1300mb: 

wrapper.java.maxmemory=1300