newItem = list.Items.Add();
newItem = list.AddItem();
SPList.AddItem() method is much more faster especially while dealing with a List with large number of items.
Refer to: SPList.Items.Add() v/s SPList.AddItem()
Just to update you need to find the Microsoft. Office. Policy assembly which contains this Information management policy job.
Once you find it, you need to update this assembly in your Web application.
Do not forget to perform an IISRESET. Sometimes it takes two to three attempts before this service starts reflecting in your Web application.
Did you change the default Diagnostics Logs location? By default, SharePoint log files are saved to the following location: "C:\Program files\Common Files\Microsoft Shared\Web Server Extensions\15\LOGS".
From the error message, it showed there was something wrong with the logs location, check it and make sure it matches the correct format.
I may recommend you to increase the interval between consecutive timer jobs .
There is no specific guideline for RAM or CPU utilization for Timer jobs .
You say that the requirement is for 10+ timer jobs running at an interval of 1 minute .
Now consider this , suppose one of the Timer job utilizes a lot of RAM and there is a high utilization spike on the ...
No there is no such guidance as it will heavily depend on the type of operations your timer job is doing. Get a Load Runner (up to 50 seat testing it is free now) and test your system without timer jobs and with them you will be able to see the impact they are having for a system under load.
Timer job might still be functional if there is no code to delete the timer job, when deactivating the feature.
You can verify the timer jobs using PowerShell or using central admin web site. Below are useful PowerShell commands
#Display All timer Jobs:
#Delete a specific timer job