Could the situation: many CPUs simultaneously read the same single file, slow down the speed of reading of...
I am running cat to separately combine file_X with a numerous number of files e.g. file_1 to file_100000000000.
Due to the large number, I distributed the job to a node with 64 CPUs to run parallelly on each CPU. Each job is ran in a sub-folder, and so there are 64 sub-folders.
To my surprise, the overall speed is much slower than expected.
As the shell script I used just direct each job to the same single file_X located in the parent directory of the 64 sub-folders, I wonder if many CPUs simultaneously read the same single file, would slow down the speed of reading of every CPU?
parallelism
asked 22 mins ago
Johnny TamJohnny Tam
120111
add a comment |
I am running cat to separately combine file_X with a numerous number of files e.g. file_1 to file_100000000000.
Due to the large number, I distributed the job to a node with 64 CPUs to run parallelly on each CPU. Each job is ran in a sub-folder, and so there are 64 sub-folders.
To my surprise, the overall speed is much slower than expected.
As the shell script I used just direct each job to the same single file_X located in the parent directory of the 64 sub-folders, I wonder if many CPUs simultaneously read the same single file, would slow down the speed of reading of every CPU?
parallelism
asked 22 mins ago
Johnny TamJohnny Tam
120111
add a comment |
I am running cat to separately combine file_X with a numerous number of files e.g. file_1 to file_100000000000.
Due to the large number, I distributed the job to a node with 64 CPUs to run parallelly on each CPU. Each job is ran in a sub-folder, and so there are 64 sub-folders.
To my surprise, the overall speed is much slower than expected.
As the shell script I used just direct each job to the same single file_X located in the parent directory of the 64 sub-folders, I wonder if many CPUs simultaneously read the same single file, would slow down the speed of reading of every CPU?
parallelism
asked 22 mins ago
Johnny TamJohnny Tam
120111
I am running cat to separately combine file_X with a numerous number of files e.g. file_1 to file_100000000000.
Due to the large number, I distributed the job to a node with 64 CPUs to run parallelly on each CPU. Each job is ran in a sub-folder, and so there are 64 sub-folders.
To my surprise, the overall speed is much slower than expected.
As the shell script I used just direct each job to the same single file_X located in the parent directory of the 64 sub-folders, I wonder if many CPUs simultaneously read the same single file, would slow down the speed of reading of every CPU?
parallelism
parallelism
asked 22 mins ago
Johnny TamJohnny Tam
120111
asked 22 mins ago
Johnny TamJohnny Tam
120111
edited 4 mins ago
Johnny Tam
asked 22 mins ago
Johnny TamJohnny Tam
120111
asked 22 mins ago
Johnny TamJohnny Tam
120111
asked 22 mins ago
Johnny TamJohnny Tam
120111
120111
add a comment |
add a comment |
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