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The things must know about Linux kernel ...

As a kernel or device driver developer one must know what Linux kernel can not

1) No access to C library
Generally, C library is large. Accessing a C lib function from kernel space is very time consuming.
It affects the kernel speed and size. So many libc functions are implemented in the kernel. Just like printf in libc is implemented as printk in kernel.

2) The kernel lacks memory protection.
Application in user space lacks memory protection. so when an application access illegal memory location, it results in segment violation. But when in kernel space segment violation occures, it results in oops. It is a major kernel error.

3) Difficult to use floating point.
When floating point arithmetic is done in user space, kernel manages the transition from integer to floating point mode. But enabling floating point in kernel, the kernel requires manually saving and restoring the floating point register. It is extra overhead for kernel.

4) Limited and small stack
Linux kernel has very small stack size. The size varies by architectures. Generally it is 8KB for 32-bit architecture and 16KB for 64-bit architecture.

5) Requires synchronization and concurrency
Linux kernel is a preemptive multitasking operating system. So scheduler schedules any process among the pool of processes. It requires synchronization between tasks. The concurrency is required when two or more processes tries to access the same resource.

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I appeared two back to back technical interviews.

The first interview was taken by a young man look like just crossed 30's.

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He checked my expertise in resume.

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Rajasthan Board 10th Results | rajedubord.nic.in | RBSE

Raj Board of Secondary Education, Rajasthan Results at rajeduboard.nic.inBoard of Secondary Education, Rajasthan Ajmer declared result of secondary examination today at 4PM official site is rajedubord.nic.in

check Secondary Examination- 2008 Result
(To be announced on July 1st, 2008 at 4:00 PM)
source
http://rajresults.nic.in/

Declared result
Praveshika Examination-2008 Result
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The history of the Board of Secondary Education Rajasthan (BSER) is a remarkable panorama of progressive record of the futurological vision for developing a dynamic system of various sub-systems of examinations and highlights of the academic excellence of the last four decades. The BSER took rapid strides for promotion and development of Secondary Education in Rajasthan, spread over 3,42,239 sq. km. and in more than 6000 schools located in 32 districts involving 8.5 lakhs students for Secondary and Senior Secondary Examination in the year 2000.

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