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From:   Ajay Kaher <akaher@vmware.com>
To:     Steven Rostedt <rostedt@goodmis.org>,
        "mhiramat@kernel.org" <mhiramat@kernel.org>,
        "shuah@kernel.org" <shuah@kernel.org>
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        "chinglinyu@google.com" <chinglinyu@google.com>,
        Nadav Amit <namit@vmware.com>,
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        Tapas Kundu <tkundu@vmware.com>,
        "er.ajay.kaher@gmail.com" <er.ajay.kaher@gmail.com>
Subject: Re: [PATCH v3 00/10] tracing: introducing eventfs
Thread-Topic: [PATCH v3 00/10] tracing: introducing eventfs
Thread-Index: AQHZlGeSoCEyu7THQ0iKwxE3Uhr81a91qBaA
Date:   Thu, 1 Jun 2023 09:07:22 +0000
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> On 01-Jun-2023, at 2:30 PM, Ajay Kaher <akaher@vmware.com> wrote:
>=20
> Events Tracing infrastructure contains lot of files, directories
> (internally in terms of inodes, dentries). And ends up by consuming
> memory in MBs. We can have multiple events of Events Tracing, which
> further requires more memory.
>=20
> Instead of creating inodes/dentries, eventfs could keep meta-data and
> skip the creation of inodes/dentries. As and when require, eventfs will
> create the inodes/dentries only for required files/directories.
> Also eventfs would delete the inodes/dentries once no more requires
> but preserve the meta data.
>=20
> Tracing events took ~9MB, with this approach it took ~4.5MB
> for ~10K files/dir.
>=20

Steve, I have used nested rw-semaphore for eventfs locking (same as in cifs=
).
As per Amit Nadav, this has to be revisited/reviewed. Please have a look an=
d
share your thoughts.

-Ajay