Re: [net-next PATCH v4 0/3] net: reserve ports for applications using fixed port

From: Eric W. Biederman
Date: Tue Feb 16 2010 - 13:49:47 EST


Octavian Purdila <opurdila@xxxxxxxxxxx> writes:

> Hi Eric, thanks for going over this.
>
> The use case (large bitmaps/lists) is different enough from what we have today
> (small bitmaps) and that is why I think that we need this new interface.
>
> If I get bitmap_parse_user correctly, for a 64k bitmap it expects a 2K comma
> separated values. That is not the most intuitively way for the user to set a
> list of ports he wants to reserve.

In this case I expect an interface of comma separated ranges would be
ideal. Typically compact, and modifiable by writing the new value to
the file.

I think the default value would be something like 32768-61000.

> Using 64K files has the same practical issues (the user would have to cat all
> 64K files to determine which ports are reserved) plus it has issues caused by
> the large number of files: significant memory overhead and also significant time
> for registering those files.

"grep -l 1 *" isn't particularly difficult, and it would be one sysctl registration
call. It is true that the sysctl memory footprint would be a pain in that case.

Eric




--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/