hi all: Thanks for your reply :) 2010/11/1 Rajat Sharma <fs.rajat@xxxxxxxxx>: >> what kind of system call will increase the size of cache? > > be clear about which cache? Are you interested in dentry cache, inode cache > or page cache? dentry cache and inode cache can grow only by access to > filesystem, access multiple files on your system. For page cache increase, > you can simple copy a very large file say 1G. > Rajat I am debugging a user mode program which is used to play multimedia. The size of cache memory is growing so high while playing files and that makes my kernel become slow, so I want to know 1. is there any function call that will increase cache usage I need to pay attention. 2. is there any function which help me to clean the caches 3. can I limit the size of cache or memory when some process, or pid, try to allocatte? > > I didnt get the purpose of your test program, perhaps you want to put memory > pressure on your system. What your test program is doing is just calling > malloc, it does nothing but grow the virtual memory area of your heap, It > wont allocate physical pages until you access the virtual address, try to > write some bytes on each allocated memory such that each 4K page is > accessed. This results in page vault in kernel and since your address is > valid so it will allocate a page for you. Typically called Demand Paging. > > If you really want to put memory pressure, try allocating memory in kernel > through kmalloc. I write this test program is try to find out which function call will effect the size of cache. appreciate your help, miloody -- To unsubscribe from this list: send an email with "unsubscribe kernelnewbies" to ecartis@xxxxxxxxxxxx Please read the FAQ at http://kernelnewbies.org/FAQ
