what is the right way to downgrade kernel

Question

I have a table where lot of threads will be operating and it is the most important table of the project, but lot of threads operate on this table.

I have a requirement that it should only insert record if count of its record(where condition is used to get the count) is less than 100. At the same time other queries should be able to read it. But since it is read by multiple threads it is able to insert more records than 100 as multiple threads can get the same count at the same time and then proceed further to insert record. I had tried using READUNCOMMITTED but it is not helping

I know SET TRANSACTION ISOLATION LEVEL SERIALIZABLE; will work, and I tired it but it slows the read operation too.

Any suggestion of how I achieve this?

Solution

I still cannot find packages of linux-image 3.2 by apt-cache search linux-images*. Where I am wrong?

On spelling. The correct command is

apt-cache policy linux-image-*

Also, the Tab Completion feature is very handy and you should learn to use it. Open a terminal and write

 sudo apt-get install linux-image- 

Then hit Tab key twice and read the list, can you see 3.2 kernel ?

do I need to install linux-header package too, are there more package I should install?

Every linux-image has its own linux-headers version, so it is preferable to install them too.

sudo apt-get install linux-headers- 

and use the same Tab Completion feature (as in linux-image- above) to locate the appropriate ones.

Comments

[amc]

possible duplicate of How to downgrade the Kernel on 11.10

[user10756]

@amc, thank you for the comment, the main question what the image-header package for, and should I install it? And how to make the downgrade from repository? I don't find answers on these question in the question your mentioned.