4 ms·
Why do applications think they can manage my memory better than my kernel?
by someone_here 16y ago
Why do applications think they can manage my memory better than my kernel?
- aaronblohowiak 16y agoBecause your kernel is general-purpose and has been tuned with certain balance between latency, throughput, and memory usage (memory management takes memory!) If your application deals with things < 4kb in size, has different performance needs &c, then it may achieve higher performance than just leaving everything up to the kernel.
- mathias_10gen 16y agoActually, MongoDB does leave memory management to the kernel by using MMAP to access data files. Most kernels will allocate a lot of memory to the disk cache, which can make it look like mongo is eating all of your ram.
- wanderr 16y agoThis. It's one of the brilliant things about mongo. The downside is that after a reboot it's up to you to get the OS to warm those caches back up.