Re: Need help with large file reading and writing.




Thanks for new solutions.

For I am using Linux system, is there still DCB file block problem? If so, how can change the parameters?

As Herman mentioned, I use the cammand "free -m" and get a output file
t.t with the information:

total: used: free: shared: buffers: cached:
Mem: 6238453760 6204731392 33722368 0 140128256 5121093632
Swap: 2147475456 1241088 2146234368
MemTotal: 6092240 kB
MemFree: 32932 kB
MemShared: 0 kB
Buffers: 136844 kB
Cached: 5000004 kB
SwapCached: 1064 kB
Active: 3127256 kB
ActiveAnon: 702984 kB
ActiveCache: 2424272 kB
Inact_dirty: 2085100 kB
Inact_laundry: 474264 kB
Inact_clean: 151596 kB
Inact_target: 1167640 kB
HighTotal: 0 kB
HighFree: 0 kB
LowTotal: 6092240 kB
LowFree: 32932 kB
SwapTotal: 2097144 kB
SwapFree: 2095932 kB
HugePages_Total: 0
HugePages_Free: 0
Hugepagesize: 2048 kB

So which parameter should and how can I change it?


Thanks all you guys
Liscon





Herman D. Knoble wrote:

Liscom: Your program looks ok; others made suggestions on Formatted I/O
but this won't likely change the problem you're having. Suggest that you
check the following:

1) Check how much RAM and correspoinding virtual storage you have.
Many people suggest that virtual storage shoud be about 2.5 times RAM.
If that number is less than 3GB then you're suspicions are likely true.
(Note the Windows Control Panel System icon will show RAM size; typically
for the System Icon, the Performance button of the Advancde tab will show
Virtual Storage allocation. If you are running under Linux try the
following commands: free -m cat /proc/cpuinfo > t.t
cat /proc/meminfo > t.t

2) Make sure you're using the latest compiler version.

3) Try a different compiler; for example, G95: http://g95.sourceforge.net/

Good luck with it.

Skip Knoble

On Thu, 13 Jul 2006 17:20:20 -0400, "news.gatech.edu" <liscon@xxxxxxxxx> wrote:

-|
-|Hello Pals:
-|
-| When I use fortran 90 code to read larger files,about 1G each, and -|write the data to other opened files with 32-bit Intel-compiler. Each -|time, I just opened 3 files simultaneously and closed unused ones. The -|code always stops at the point of 10 files reading. I am not sure it is -|the compiler problem about the limitation of buffer memory.
-|
-|Thanks very much
-|
-|Liscon
-|
-|
-|Simple code:
-|
-| open(unit=18,file="aux.out")
-| do i=1,10
-| open(unit=101+i,file="fort.1+i") !old file; unit and file name just -|for simplicity
-|
-| open(unit=1001+i,file="fort.101+i") !New file
-|
-| do j=1,EN ! number of lines wrote to the new file
-| read(101+i,format)n1,n2,n3,n4,n5,n6,n7
-| write(1001+i,format)n1,n2,n3,n4,n5,n6,n7
-| end o
-|
-| do j=EN+1,N ! number of lines left,N=total lines of old file
-| read(101+i,format)n1,n2,n3,n4,n5,n6,n7
-| write(1001+i,format)n1,n2,n3,n4,n5,n6,n7
-| end do
-|
-| close(101+i)
-| close(1001+i)
-|
-| end do


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