Re: Shared memory file copying to another server

From: Seth (bugs_at_[hidden])
Date: 2024-11-08 23:23:13

On Fri, Nov 8, 2024, at 5:19 AM, Murali Kishore via Boost wrote:
> Hi Ion,
>
> I have tried one experiment, copying shared memory from one linux server to
> another linux server; both are identical w.r.t os and memory configuration.
> I am able to open shared memory and access stored classes in another server.
>
> want to check with you on this, is there any issues or this procedure is ok
> to use or any expected abnormal behaviours later. Please help to understand
> how this works if both servers are identical.

There's no logical distinction between creating a shared memory segment in one process, ending the process and reopening the same segment in a new process and what you describe.

I'd personally replace `managed_shared_memory` with `managed_mapped_file` so the intent of treating the mapped segment as a file becomes more clear. In effect, shared memory on linux is just a file in a special kind of filesystem, anyways.

Also, you're responsible for keeping track of consistency during copy (e.g. if you copy the data during a mutation, you may incur undefined behavior on use (incl. opening), and/or you may encounter a stuck lock).

Seth