ServerBuddies Support Blog

MX priority

The relative priority of an MX server is strong-minded by the preference number present in the DNS MX record. When a remote client does an MX lookup for the domain name, it gets a list of servers and their first choice numbers. The MX record with the smallest first choice number has the highest precedence and is the first server to be tried. The remote client will go down the list of servers until it successfully delivers the message or gets permanently rejected due to an inaccessible server or if the mail account does not exist on that server. If there is more than one entry with the same preference number, all of those must be tried before moving on to lower-priority entries.

renice — alter priority of running processes

Renice alters the scheduling priority of one or more running processes. The following who parameters are interpreted as process ID’s, process group ID’s, or user names. a process group causes all processes in the process group to have their scheduling priority altered. a user causes all processes owned by the user to have their scheduling priority altered. By default, the processes to be affected are specified by their process ID’s.

For example,

would change the priority of process ID’s 987 and 32, and all processes owned by users daemon and root.

Users other than the super-user may only alter the priority of processes they own, and can only monotonically increase their “nice value” within the range 0 to PRIO_MAX (20). (This prevents overriding administrative fiats.) The super-user may alter the priority of any process and set the priority to any value in the range PRIO_MIN (?20) to PRIO_MAX. Useful priorities are: 20 (the affected processes will run only when nothing else in the system wants to), 0 (the “base” scheduling priority), anything negative (to make things go very fast).

Change priority of swap files

You can check the current priority of the swap file from /proc/swaps.

Inorder to change the priority of the swap partitions, you need to edit the “fstab” and append the new priority. If you have the fstab entry for your swap file /swap1 as:

then append the following:

where x is the new priority you have set.

You can re-mount it by using ‘mount -a’ command.

Change priority of swap files

You can check the current priority of the swap file from /proc/swaps.

Inorder to change the priority of the swap partitions, you need to edit the “fstab” and append the new priority. If you have the fstab entry for your swap file /swap1 as:

then append the following:

where x is the new priority you have set.

You can re-mount it by using ‘mount -a’ command.