A website about linux, kvm,gluster, ceph, kubernetes and programming
I have seen reports saying that – under some scenarios, the KVM guest system reports I/O errors in its ‘dmesg’ against virtio block devices and also, some times it cause the filesystems inside the guest to go ‘READONLY’ mode. Tracking such issues are a bit difficult and its a pain. I believe we should make …
Red Black Tree algorithm is famous in computer world.. Obviously smartly designed software adopt it.. It happened with the linux kernel as well.. so a study on it. I will be continuing the rest in other article .. Here is an intro on it. [pdf id=5400]
Q) “I got an ‘errno’ returned from the system call and want to map to the exact error message or to the error string which is human readable.. How can I do that ?? This was answered quite a few times, however, I forgot to share it here, but not this time. Here is …
Yes, instead of pointing to urls which slowly conclude the things, I will give a quick start here: Why a quick start/read:? At times it is not a good choice for some people to go and read all the document and get it done, rather they would like to know the basic syntax/usage and a …
Yes, simple , Isn’t it ? but it may not be simple for someone who just started with it, so the post You could try something like below to generate a module # stap -k -p4 script.stp -k Keep the temporary directory after all processing. This may be useful in order to examine the …
Ah…… Why I forgot to write about dropwatch ? “Packets are dropped” , these strings are quite common in IT world, but how to prove it and where it is dropped ? Till now, people were behind ‘netstat’ ( for ex:netstat -s ) utiilty to see it , but retrieving more information on where it …
Today one of my friend asked me to interpret below assembly instruction for him, so this post 🙂 The instruction have below format, It is one of indirect addressing modes, so this should be read in such a way that, What that basically means is that IR * Width + offset
Qemu provides a new “tracing” mechanism which can be used in conjuction with several backends.. Especially useful to make use of it via “system Tap” which shipped with most of the distros.. The trace points are really useful when debugging or when doing performance analysis. The trace events can be enabled/disabled at run time.. …
Yes, there is an easy way to check list of options currently compiled in your kernel. It is as simple as that visting “/boot/config-” file. That said, have a look at below snip in my system. [root@humbles-lap ~]# cat /boot/config-2.6.35. config-2.6.35.14-97.fc14.x86_64 config-2.6.35.6-48.fc14.x86_64 config-2.6.35.9-64.fc14.x86_64 [root@humbles-lap ~]# The above are the files which contains information about compiled …
Let’s start with some GCC commands as shown below. How-ever it won’t give you all the resulted files in each stage, for ex: preprocessor files. For that, I use below GCC option to generate different output files of my source. As mentioned in “man’ page it will generate “.i”, “s”, “.o” files .. Ex: #Examine …