[Spread-users] Increasing the size of the group name

[James J. Wagner]

> -----Original Message-----
> From: spread-users-admin at lists.spread.org
> [mailto:spread-users-admin at lists.spread.org]On Behalf Of Ryan Caudy
> Sent: Friday, January 23, 2004 2:37 PM
> To: James J. Wagner
> Cc: spread-users at lists.spread.org
> Subject: Re: [Spread-users] Increasing the size of the group name
>
>
> Just a guess, but it seems likely from the way its used that
> as long as
> the increase to the private name size is a multiple of 4
> bytes (for 32
> bit architectures), you shouldn't see bus errors.  That is, make sure
> the max private name is a multiple of 4, and the max group
> name as well,
> for which you have the formula you mentioned.  If this workaround
> doesn't work, let me know.

Well that seems to be the weird thing. MAX_PRIVATE_NAME can't be a multiple of
4. 10 is how the distro is set, and I had to set it to 30. 32 didn't work.

Ah... since the MAX_GROUP_NAME = 2 + MAX_PRIVATE_NAME(30) + MAX_PROC_NAME(20),
*IT* does equal a power of 4... 52. And it also equals a power of 4 when the
private name is set to 10.

Assuming that is true, good to know. That way if I have to increase it again,
I'll know how to calculate a valid number.

>
> As far as I know, the reason for the two separate definitions
> is to hide
> the "real" formula from the user, and give a very simple set
> of headers
> to be used by clients programs linking with libspread.  I
> agree that it
> may need further consideration.

Yeah... probably a good idea if clients don't have to configure things. But if
they do, then having the formulas helps.

	Thanks,
		James.

>
> --Ryan
>
> James J. Wagner wrote:
>
> > No, I do need a larger group name. Changing the size of the
> MAX_PRIVATE_NAME
> > changes the size of the MAX_GROUP_NAME because the
> MAX_GROUP_NAME is defined as
> >
> > 	#define MAX_GROUP_NAME (1+MAX_PRIVATE_NAME+1+MAX_PROC_NAME)
> >
> > At least it is defined as that in spread_params.h. It is
> hardcoded to 32 in
> > sp.h, but I changed it to the above (so it would adjust).
> >
> > Good to know you aren't having problems on linux. That
> gives me hope that once I
> > got pass the bus error (by changing the size from 32 to 30)
> that things should
> > work.
> >
> > 	Thanks,
> > 		James.
> >
> >
> >>-----Original Message-----
> >>From: Greg Shebert [mailto:gshebert at efs-us.com]
> >>Sent: Friday, January 23, 2004 1:46 PM
> >>To: James J. Wagner
> >>Subject: Re: [Spread-users] Increasing the size of the group name
> >>
> >>
> >>hey there
> >>
> >>i think what you are saying, first of all, is that you need a larger
> >>private name, not a larger group name... this will make the
> >>size of the
> >>private group name larger but the group name stays the same
> >>
> >>i ran into the same problem and upped the private name to 32... on
> >>solaris i started having bus errors all over the place...
> >>
> >>some of the daemon code is poorly written and makes some assumptions
> >>about things being aligned on word boundarys... messing with
> >>the private
> >>name size changes the alignments and causes your bus errors...
> >>
> >>i've submitted the crash bugs and am hoping it will be fixed
> >>in a later
> >>version...
> >>
> >>other than the solaris crash bugs, i've been running on linux
> >>with these
> >>increased sizes with no problems
> >>
> >>-gre-g
> >>
> >>
> >>On Fri, 2004-01-23 at 14:26, James J. Wagner wrote:
> >>
> >>>Running on Solaris.
> >>>
> >>>I need to increase the size of the group name. I have done so by
> >>>increasing MAX_PRIVATE_NAME from 10 to 30. This *seems* to
> work (has
> >>>worked so far in limited testing). A few comments though:
> >>>
> >>> 1) Increasing it to 32 causes a bus error
> >>>
> >>> 2) Increasing it to 30 works - so there is some set of
> >>
> >>magic numbers
> >>
> >>>that seem to work
> >>>
> >>> 3) I noticed this constant is defined in both sp.h and
> >>>spread_params.h - why is this defined in two places?
> >>>
> >>> 4) While modifying these two files I noticed that sp.h defines
> >>>MAX_GROUP_NAME to be 32, whereas spread_params.h defines it to be a
> >>>formula. I updated sp.h so that it also uses a formula,
> >>
> >>thus adjusting
> >>
> >>>the value as I increase MAX_PRIVATE_NAME.
> >>>
> >>>A couple of questions:
> >>>
> >>>1) Are there any known issues associated with increasing
> the size of
> >>>the group name?
> >>>
> >>>2) Is there a way to know what will work (30 vs 32, etc.)
> >>
> >>or if I need
> >>
> >>>to make it larger do I need to just use a trial and error approach?
> >>>
> >>>    Thanks,
> >>>        James.
> >>>
> >>
> >
> >
> > _______________________________________________
> > Spread-users mailing list
> > Spread-users at lists.spread.org
> > http://lists.spread.org/mailman/listinfo/spread-users
> >
>
> --
> Ryan W. Caudy
> Center for Networking and Distributed Systems
> Department of Computer Science
> Johns Hopkins University
>
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