DASD - Hard Drive Requirements for InveStore


The InveStore product line has specific requirements for DASD storage on the Windows server that it is installed on. DASD stands for "Direct Access Storage Device" which refers to the magnetic hard drive on which your Windows 2000/XP/2003 server is installed. The following is a discussion on these requirements:




Windows PAGEFILE serves as virtual memory and is used to swap pages to and from memory to balance the use of physical RAM between various processes on the system. PAGEFILE uses DASD or magnetic hard drive disk space for its operations.


InveStore requires you to allocate a minimum of 48 MB of this PAGEFILE for InveStore operations -- this is in addition to PAGEFILE requirements of Windows or other programs installed on this server. (PAGEFILE requirements are calculated at: 2 X RAM)


To set the PAGEFILE, open "My Computer" > "Control Panel" > "System". You'll see a tab for "Performance". Under this tab it displays a section for "Virtual Memory". This will show your current settings for the Windows PAGEFILE. Select "Change" to make modifications to this area.


It is recommended that for most Windows servers the PAGEFILE be set to a minimum of 500 MB. This is normally sufficient for both the Windows operating system and for the InveStore requirements.


At least 15MB DASD storage per volume for directory caching


The InveStore file system creates and uses what are referred to as "cache" structures on the magnetic hard drive (DASD) of the Windows server.  This "cache" structure ONLY contains directory information and file location of the data that is on each of the storage media. InveStore uses this "cache" to speed up the processing of requests on the storage library.


You should allow for a maximum of 15MB of DASD hard drive space for each volume (or disk side) that you have mounted in the storage library.


50MB of free DASD storage


You should always maintain a minimum of 50MB of free hard drive space at all times. Disk space is essential not only of Windows’s operations, but for InveStore to be able to track and access the media in the storage library properly.


The DASD drive used for caching should be a separate drive or partition from that used by the Windows virtual memory manager.


If the free hard drive space on the partition that Window’s PAGEFILE is set to is limited (i.e. you do not have sufficient free space for the above requirements), you should install InveStore on a separate drive partition from that which is setup for PAGEFILE. This will help avoid a situation where the server runs out of free disk space. Running out of free hard drive space will cause Windows to crash.