[Info-vax] SAMBA really sloooow on OVMS Integrity. Any Ideas????

[Len Whitwer]

On Aug 18, 8:11 am, koeh... at eisner.nospam.encompasserve.org (Bob
Koehler) wrote:
> In article <b10eda82-8d64-428b-805b-71ccd0ca4... at x20g2000pro.googlegroups.com>, Len Whitwer <l... at psds.com> writes:
>
>
>
> > We build from Samba download on HP's site. (What is an alignment fault
> > and how can I tell if we are getting them?)
>
>    An alignment fault happens when you access an address that is not
>    an even multiple of the data size.  When a compiler can see that
>    you're going to do this, it should generate the necessary code
>    to access the surrounding larger data size and then strip off the
>    desired data.  When a compiler can't see this, or if the compiler
>    just isn't that robust, the instruction that accesses the data will
>    cause an alignment fault, which will get trapped, the data fetch
>    will be fixed up, and then the fault dismissed.  This takes longer
>    than just fixing up the access in the first place.
>
>    Sometimes code must interface to external data streams that are
>    defined in poorly aligned manners.  Internal data stores should
>    always be allowed to be aligned (compilers like to do that for you).
>
>    The best way to access a poorly alined external data stream is to
>    grab the whole thing, then code the movement from an unaligned to
>    an aligned copy (or back) in such a manner as not to create alignment
>    faults.
>
>    There are tools in VMS to monitor alignment faults, but I've never
>    used them so someone else will have to chime in here.

Hi All:

Thanks very much for all the input. We did the download from HP's webb
site and it is verson 1.2. We are going to do a fresh build from
scratch (OVMS ver 8.4 and Samba 1.2) just to make sure we have a solid
foundation. Still working on it.

Len