cpu floating operations cost

Posted by wiso on Stack Overflow See other posts from Stack Overflow or by wiso
Published on 2010-05-22T10:58:54Z Indexed on 2010/05/22 11:00 UTC
Read the original article Hit count: 258

Filed under:

floating-point

|

cpu

|

cost

|

Operations

I'm interesting in the time cost on a modern desktop cpu of some floating point operations in order to optimize a mathematical evaluation. In particular I'm interested on the comparison between complex operations like exp, log and simple operation like +, *, /.

I tried to search for these information, but I can't find a source.

© Stack Overflow or respective owner

Related posts about floating-point

Comparing floating point values

as seen on Stack Overflow - Search for 'Stack Overflow'
I just read a statement about the floating point value comparison Floating point values shall not be compared using either the == or != operators. Most floating point values have no exact binary representation and have a limited precision. If so what is the best method for comparing two floating… >>> More
understanding floating point variables

as seen on Stack Overflow - Search for 'Stack Overflow'
There is some problem, i can't understand anyway. look at this code please <script type="text/javascript"> function math(x) { var y; y = x*10; alert(y); } </script> <input type="button" onclick="math(0.011)"> What must be alerted after i click on button? i think 0.11… >>> More
floating point hex octal binary

as seen on Stack Overflow - Search for 'Stack Overflow'
Hi, I am working on a calculator that allows you to perform calculations past the decimal point in octal, hexadecimal, binary, and of course decimal. I am having trouble though finding a way to convert floating point decimal numbers to floating point hexadecimal, octal, binary and vice versa. The… >>> More
What is a Bias Value of Floating Point Numbers?

as seen on Stack Overflow - Search for 'Stack Overflow'
In learning how floating point numbers are represented in computers I have come across the term "bias value" that I do not quite understand. The bias value in floating point numbers has to do with the negative and positiveness of the exponent part of a floating point number. The bias value of a… >>> More
Why are floating point values so prolific?

as seen on Stack Overflow - Search for 'Stack Overflow'
So, title says it all. Why are floating point values so prolific in computer programming. Due to problems like rounding errors, and not being able to even accurately represent numbers such as 0.1, I really can't see how they got as far as they did. I understand that the computation is faster… >>> More

Related posts about cpu

Speedstep and Intel x5570?

as seen on Server Fault - Search for 'Server Fault'
Hi, My new server has 2 x X5570 CPUs. Now here is the output of grep -i hz /proc/cpuinfo model name : Intel(R) Xeon(R) CPU X5570 @ 2.93GHz cpu MHz : 1600.231 model name : Intel(R) Xeon(R) CPU X5570 @ 2.93GHz cpu MHz : 1600.231 model name : Intel(R) Xeon(R) CPU … >>> More
VMware ESXi - varying CPU time (CPU reservation)

as seen on Server Fault - Search for 'Server Fault'
Hello! I'm running FreeBSD 7.2 under VMware ESXi 3.5. Host has 2 physical CPUs and the BSD box is currently the only running VM. Only one virtual CPU is assigned to the VM. When measuring CPU time of a specific program, I get very different results from time to time. Processor usage is reported… >>> More
How to calculate CPU % based on raw CPU ticks in SNMP

as seen on Server Fault - Search for 'Server Fault'
According to http://net-snmp.sourceforge.net/docs/mibs/ucdavis.html#scalar_notcurrent ssCpuUser, ssCpuSystem, ssCpuIdle, etc are deprecated in favor of the raw variants (ssCpuRawUser, etc). The former values (which don't cover things like nice, wait, kernel, interrupt, etc) returned a percentage… >>> More
disparity between `top`'s given CPU % and process CPU usage total

as seen on Super User - Search for 'Super User'
I've noticed that there are sometimes (large) differences between the reported total CPU usage and a summation of the per-process CPU utilization given by apps like top and wmtop. As an example: I recently ran a git filter-branch --index-filter on a fairly large repo, with the index-filter command… >>> More
How to read oom-killer syslog messages?

as seen on Server Fault - Search for 'Server Fault'
I have a Ubuntu 12.04 server which sometimes dies completely - no SSH, no ping, nothing until it is physically rebooted. After the reboot, I see in syslog that the oom-killer killed, well, pretty much everything. There's a lot of detailed memory usage information in them. How do I read these logs… >>> More