How do I find bottlenecks in Linux?

We can find bottleneck in linux server performance using following method..

1. Take the output of TOP & mem, vmstat commands in one notepad.
2. Take sar output of 3 months.
3. check the variation in processes & usage at the time of implementation or change.
4. If the load is unusual since the change.

How do I find network bottlenecks?

Check the interfaces towards each (source and destination) according to how the router or L3 switch forwards the packet. Check for interface errors, bits-per-second, packets-per-second, and if you have an overloaded interface you may have found your bottleneck.