[syslinux] pxelinux 4.10-pre17 HTTP performance (cptime)

[Gene Cumm]

On Fri, Dec 30, 2011 at 07:26, Schlomo Schapiro <schlomo at schapiro.org> wrote:
> Hi,
>
> thanks for writing cptime, after manually adding it to the Makefile of a
> lwip git checkout it compiled fine (same about prdhcp) (only isohybrid
> complained about a missing uuid/uuid.h)...

Fix already submitted and pending.

> I have a 64bit VM with VMXNET3 and go there this result:

Guest OS hint shouldn't matter much.  The VMXNET3 may.

> [image: cptime.png]
>
> (can everybody see the picture?)

Attached but sufficient.

> The download of a 180MB large file (Parted Magic initrd) takes between 60
> and 72 seconds, which is about 2.6 to 2.3 MiB/s.
>
> Can this go any faster? Or is this the most that we can get out of a
> preboot environment?

Is this via HTTP or TFTP?  I'm betting the latter and you've got about
double the best performance I've seen.

> BTW, what is the meaning of the +0, +1, -1 lines? Maybe you add there some
> hint to make it self-explanatory.

It's due to the low precision of the timer that was available when I
first wrote it (55 ms per tick, iirc).  I should change it to not put
that out, depending on the number of ticks (ie, if it's over something
like 100 or 1000).

-- 
-Gene