I am trying to write zeroes to the hdd using a c program. I don't want to use the dd or ddrescue or any such inbuilt program because of reasons like real time progress, writing custom patterns. (my program is more like an erasure application, but does only zero fill).
here are the steps which i have followed. (I am executing under root).
Linux version used is ubuntu with (Intrepid) 8.10, with 2.6.27-7-generic.
opened the device /dev/sda using open call.
Code:
fd = open("/dev/sda", O_WRONLY);
and called a write call with
Code:
write(fd,buff,512);
The write call never fails for some strange reasons. It always returns 512 even in the case of a bad hdd connected to system. (The dmesg shows either the hdd is bad or not responding the write requests, or has I/O errors, or has sectors errors, or has failed the hard / soft reset operations).
I have tried using errno to get the error value, but nothing returns the error condition. Is that something i am missing?
I want to do a low level format like in windows (C:\format c:) but I don't know how it works in unix or linux.. Can somebody help me ? thnx :) (3 Replies)
Hi,
What is the best reference that gives in detail on nic cards configuration , assigning multiple ip addresses to a single interface, netlink library etc and all basic stuff at this level..?
Thanks (2 Replies)
Hello All
I have a system running AIX 61 shared uncapped partition (with 11 physical processors, 24 Virtual 72GB of Memory) .
The output from NMON, vmstat show a high run queue (60+) for continous periods of time intervals, but NO paging, relatively low I/o (6000) , CPU % is 40, Low network.... (9 Replies)
Hi friends,
I hope everyone is fine and doing well. I queried in my previous thread about the low-level qualities of C/C++ languages.I really thank you people for explaining, it was really helpful. One more ambiquity that I have in my mind is regarding the unix system calls like open, creat,... (1 Reply)
Hi friends,
I hope everyone is doing well and fine. I have always been hearing that C/C++ are relatively low-level as compared to Java/C# etc. Could you please tell me some low-level qualities of C/C++? And I think disk deframenters are written in C/C++, please correct me if I am wrong. And please... (5 Replies)
How to use X11 without Xlib not XCB? How draw window directly on low level?
I must use anyway window manager like Motif?
I have ridden that X11 has server-client architecture, client send via TCP/IP to port 6000 request for primitives and get replies.
Where is detailed description of it? In X11... (0 Replies)
Discussion started by: AndrzejB
0 Replies
LEARN ABOUT DEBIAN
stress
STRESS(1) User Commands STRESS(1)NAME
stress - tool to impose load on and stress test systems
SYNOPSIS
stress [OPTION [ARG]] ...
DESCRIPTION
`stress' imposes certain types of compute stress on your system
-?, --help
show this help statement
--version
show version statement
-v, --verbose
be verbose
-q, --quiet
be quiet
-n, --dry-run
show what would have been done
-t, --timeout N
timeout after N seconds
--backoff N
wait factor of N microseconds before work starts
-c, --cpu N
spawn N workers spinning on sqrt()
-i, --io N
spawn N workers spinning on sync()
-m, --vm N
spawn N workers spinning on malloc()/free()
--vm-bytes B
malloc B bytes per vm worker (default is 256MB)
--vm-stride B
touch a byte every B bytes (default is 4096)
--vm-hang N
sleep N secs before free (default is none, 0 is inf)
--vm-keep
redirty memory instead of freeing and reallocating
-d, --hdd N
spawn N workers spinning on write()/unlink()
--hdd-bytes B
write B bytes per hdd worker (default is 1GB)
--hdd-noclean
do not unlink files created by hdd workers
Example: stress --cpu 8 --io 4 --vm 2 --vm-bytes 128M --timeout 10s
Note: Numbers may be suffixed with s,m,h,d,y (time) or B,K,M,G (size).
SEE ALSO
The full documentation for stress is maintained as a Texinfo manual. If the info and stress programs are properly installed at your site,
the command
info stress
should give you access to the complete manual.
stress 1.0.1 August 2009 STRESS(1)
02-21-2010
