multiple processes read the same file at the same time, cannot read file

[liugs0213]

Alluxio Version:
2.9.0

Describe the bug
same issue: #14007

a process reads the directory: 70s
two processes reads the directory: 160s
three processes reads the directory: two process error,a process is slow.

To Reproduce
Three processes mount a fuse to read the same directory

Expected behavior
A clear and concise description of what you expected to happen.

Urgency
Describe the impact and urgency of the bug.

Are you planning to fix it
Please indicate if you are already working on a PR.

Additional context
Add any other context about the problem here.

[Kai-Zhang]

@LuQQiu can you share more information on the slow reading problem?

[LuQQiu]

fuse_flame.tar.gz
worker_flame.tar.gz
fuse_jstack.log

[LuQQiu]

Likely same issue as before, multiple Files shared the same FileInStream and do many of the seek() operation.
The current Alluxio system does not support seek efficiently

[LuQQiu]

One idea is to use BufferedSeeakbleInputStream, it's a way to use memory to improve performance.
When applications do
seek() -> read 128KB -> seek() -> read 128KB
it can change to read e.g. 2MB -> seek inside the 2MB is efficient.
The cache size is tunable