I analysed disk performance with blktrace and get some data:
read:
Code:
8,3 4 2141 2.882115217 3342 Q R 195732187 + 32 [cat]
8,3 4 2142 2.882116411 3342 G R 195732187 + 32 [cat]
8,3 4 2144 2.882117647 3342 I R 195732187 + 32 [cat]
8,3 4 2145 2.882118965 3342 D R 195732187 + 32 [cat]
8,3 4 2149 2.884145702 0 C R 195732187 + 32 [0]
write:
Code:
8,3 4 43622 5.305507398 3436 Q W 17805895 + 8 [bash]
8,3 4 43623 5.305508277 3436 G W 17805895 + 8 [bash]
8,3 4 43624 5.305508574 3436 I W 17805895 + 8 [bash]
8,3 2 414 5.306695591 0 D W 17805895 + 16 [swapper]
8,3 2 418 5.307020642 0 C W 17805895 + 16 [0]
And, d2c time of one read request is 0.002026737s. On the other hand, d2c time of one write request is 0.000325051s. It show: read time > write time. Is it right? why? I have no idea.
Hi,
Is mv (move) command quicker than cp (copy command)?
I have large files and I want to know if mv actually copy the data to a new file then deletes the old or whether it just alters information the file system without physically moving data - Unfortuanately I don't have large files to test... (2 Replies)
Hello,
I have a Supermicro server with a P4SCI mother board running Debian Sarge 3.1. This is the "dmidecode" output related to RAM info:
RAM speed information is incomplete.. "Current Speed: Unknown", is there anyway/soft to get the speed of installed RAM modules? thanks!!
Regards :)... (0 Replies)
If a file size increases in Linux/UNIX to say in GB's then will there be a decrease in write speed.
I mean will it take more time to write to a large file then to a small one??
Please clarify?
Thanks in advance (2 Replies)
hi
i'm greping the files with sepefic keyword, where the file is of too big. Assume there are 10 days log file each of more than 200mb. i've to grep all those files with a specific keywords.
for example,
1. i'll grep for error message
2. after the i'll do one more grep for keyword... (4 Replies)
Being a novice user to linux i m little unaware of how would i check disk read write speed.
One of my mate is suggesting to create a file using dd command and check how much time it takes to create a 30 gb file .
I think this has a little sense however i would also like to take your reviews... (5 Replies)
I am now on Kernel 2.6.32-26
For me 16x CD write speed is okay.
I have old hardware which was able to write DVDs at 1x, back in previous linux version.
Now, I dont get speed of less than 4x.
Tested on k3b, xfburn, and brasero. But all start at bottom 4x write speed. k3b forced back to... (0 Replies)
Hi,
I have to grep string from 20 - 30 files each carries 200 - 300 MB size and append to the
file. How to speed the
grepping time.
cat catalina.out_2012_01_01 | grep "xxxxx" >> backup.txt
PLZ, Suggest me,
Regards,
Nanthagopal A (5 Replies)
Hi,
We have two servers in scenario (vmsoldot01 is Oracle VM with Linux and tldtppod15 is physical Linux server). One NAS share is mounted on both servers with similar permissions and access. But READ speed is too bad on virtual in comparison to physical server.
While trying to diagnose this, I... (2 Replies)
Hello All,
I am building a real time parser for a log file in my application.
The log file is continuously written at a very fast pace and gets rolled over every 10 minutes.
I have measured the speed and observed that around 1000 lines are written to it every second, each line about 30-40... (7 Replies)
Discussion started by: cool.aquarian
7 Replies
LEARN ABOUT DEBIAN
mcxconvert
mcx convert(1) USER COMMANDS mcx convert(1)
NAME
mcx convert - convert between mcx storage types
SYNOPSIS
mcx convert <matrix-file-in> <matrix-file-out>
mcx convert [--write-binary] --cone-to-stack <cat-file-in> <cat-file-out>
mcx convert [--write-binary] --stack-to-cone <cat-file-in> <cat-file-out>
mcxconvert is not in actual fact a program. This manual page documents the behaviour and options of the mcx program when invoked in mode
convert. The options -h, --apropos, --version, -set, --nop, -progress <num> are accessible in all mcx modes. They are described in the mcx
manual page.
mcx convert [--cone-to-stack (transform cone file to stack file)] [--stack-to-cone (transform stack file to cone file)] [--write-binary
(output native binary format)] [--cat (read and write cat format)] [-cat-max <num> (limit the stack conversion to <num> matrices)]
In the two-argument invocation without additional arguments, mcx convert converts from the format found in the first file to the other for-
mat, i.e. from native interchange to native binary format or the other way around. When querying with the -q option, mcx{convert} will out-
put a one-line synopsis describing the matrix in the argument. The --cone-to-stack and --stack-to-cone options convert between the two types
of concatenated output provided by mclcm.
DESCRIPTION
The mcl libraries make extensive use of matrices. Matrices are used to encode graphs, matrices and clusterings. They can be stored either
in interchange or in binary format. The latter is somewhat more efficient in storage and much faster in both reading and writing, but the
default is interchange format.
The mcl input routines recognize the type of storage they are dealing with. If you want to convert a matrix to the other storage type, sim-
ply specify the file name of the matrix you want to convert. mcx convert will recognize its type, and write the other type to the file
specified as the second argument.
OPTIONS
--cone-to-stack (transform cone file to stack file)
This option requires two trailing options, the names of respectively the source cone file and the target stack file.
--stack-to-cone (transform stack file to cone file)
This option requires two trailing options, the names of respectively the source stack file and the target cone file.
--cat (read and write cat format)
-cat-max <num> (limit the stack conversion to <num> matrices)
--write-binary (output native binary format)
This option is only useful with either of the options --cone-to-stack, --stack-to-cone, or --cat.
AUTHOR
Stijn van Dongen.
SEE ALSO
mcxio(5), and mclfamily(7) for an overview of all the documentation and the utilities in the mcl family.
mcx convert 12-068 8 Mar 2012 mcx convert(1)