On Mon, Feb 28, 2022 at 10:49 PM David Laight David.Laight@aculab.com wrote:
From: Abhinav Kumar
Sent: 28 February 2022 21:38
...
We also did some profiling around how much increasing the block size helps and here is the data:
Block size cost
4KB 229s 8KB 86s
You must have an O(n^2) operation in there - find it.
The problem is how the devcoredump/sysfs interface works, which results in "re-rendering" the output for each block.. it's fine for moderate size sysfs files, but scales quite badly once you get into couple MB size sysfs files.
It could be fixed by having some way to keep state across successive read callbacks.
BR, -R
David
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