CLAYTON@XRT.UPENN.EDU ("Clayton, Paul D.") (06/01/88)
In noting the recent sequence of messages concerning the use of 'idle process' killers and what is the assumed benifit(s) of these type programs, the list of answers seem to be missing some important aspects. Aside from the security, which I grant is a major one and is large enough by itself to implement a killer process, the various resources of the VAX have to be looked at. The list starts with space in the page and swap files taken for the process. This space is dedicated to the process that has caused the Swapper/Pagefaulter to allocate the space for the process. I have used upwards of three (3) RA-81 disks for nothing but PAGE/SWAP files for the systems in a VAXCluster. Next comes any outstanding entries in queues to various devices, such as the terminal the user is logged into, a disk device, or timer/AST entry. This takes up POOL, or as we now know it 'Ocean'. This takes memory and 'could' length the time needed to go through a particular queue. My past systems had pool space boarding on 2MB for BOTH PAGE and NONPAGE. Then there is the physical memory that is unavailable for general consumption due to the process not doing anything, and the SWAPPER not getting to the point of looking for processes to out swap. Memory prices are down, but the 8XXX systems still have relative high prices for memory. The problem in determining the impact of the items listed above is not an easy one to solve. This is due to it being largely based on how the program designer and coder wrote the applications on your systems. If its in-house systems then you stand a chance of finding out how a program works. For the third party packages, its a game of detective and making assumptions. These factors, to me, are a large incentive to keep the list of 'active' users on the systems at any one time to those that are actually doing something and to get rid of the ones that have taken breaks and did not, or forgot, to log off the system(s). The above is listed as food for thought. :-) pdc Paul D. Clayton Address - CLAYTON%XRT@CIS.UPENN.EDU Disclaimer: All thoughts and statements here are my own and NOT those of my employer, and are also not based on, or contain, restricted information.