How do you pre allocate memory to a process in solaris?

Question

My problem is: I have a perl script which uses lot of memory (expected behaviour because of caching). But, I noticed that the more I do caching, slower it gets and the process spends most of the time in sleep mode. I thought pre-allocating memory to the process might speed up the performance. Does someone have any ideas here? Update: I think I am not being very clear here. I will put question in clearer way: I am not looking for the ways of pre-allocating inside the perl script. I dont think that would help me much here. What I am interested in is a way to tell OS to allocate X amount of memory for my perl script so that it does not have to compete with other processes coming in later. Assume that I cant get away with the memory usage. Although, I am exploring ways of reducing that too but dont expect much improvement there. FYI, I am working on a solaris 10 machine. JavaScript questions and answers, JavaScript questions pdf, JavaScript question bank, JavaScript questions and answers pdf, mcq on JavaScript pdf, JavaScript questions and solutions, JavaScript mcq Test , Interview JavaScript questions, JavaScript Questions for Interview, JavaScript MCQ (Multiple Choice Questions)

Answer 1

What I gathered from your posting and comments is this: Your program gets slow when memory use rises Your pogram increasingly spends time sleeping, not computing. Most likely eplanation: Sleeping means waiting for a resource to become available. In this case the resource most likely is memory. Use the vmstat 1 command to verify. Have a look at the sr column. If it goes beyond ~150 consistently the system is desperate to free pages to satisfy demand. This is accompanied by high activity in the pi, po and fr columns. If this is in fact the case, your best choices are: Upgrade system memory to meet demand Reduce memory usage to a level appropiate for the system at hand. Preallocating memory will not help. In either case memory demand will exceed the available main memory at some point. The kernel will then have to decide which pages need to be in memory now and which pages may be cleared and reused for the more urgently needed pages. If all regularily needed pages (the working set) exceeds the size of main memory, the system is constantly moving pages from and to secondary storage (swap). The system is then said to be thrashing and spends not much time doing useful work. There is nothing you can do about this execept adding memory or using less of it.