[Zope] Re: ZEO and 2gb max limit for linux .. not for solaris etc.

[Jørgen Skogstad]

Sven Hohage wrote:
> 
> Hallo Jorgen,
> I write you cause I've got a question about Zope.
> You've posted on the mailing list on my question with the filesize of
> the data.fs or in ZEO ZSS.
> My problem is that I'd like to know which Unix - versions don't have
> this filesize limitations and if there is a linux version without that
> limit.
> Or do you know another way to solve this problem??
>                                          Many thanks
>                                                          Sven

Hmm.. well .. I can tell you what I know as of today. Linux
has this limitation as of today. At least all the variants I 
have come over (mostly Red Hat and Suse). The limitation is in
the filesystem implementation itself; meaning that the number
of "references" that can be created cannot exceed the address
limit of 2gb. 

Solaris does not have this limitation and neither does Hp-Ux
or SGI Irix. I know previous versions of SunOS (v4.x) had the
same limitation as linux is experiencing today.

Though.. there are ways "around" the problem. Though; all different
over the variuos unix versions as of today. When running Zope
you really don't have much choice on linux. When you hit the
2gb barrier .. you have problems. I have not tried it .. but 
as I can recall there was a product for Zope that made it possible
to "mount" several databases at once .. though it was beta.

.. this might solve a problem .. and would from my point of view
be a nice way to go. This way; the administrator of the system
also have some choices as to where he want to put his data. 
Then you can move certain object databases to fast storage .. 
and so forth.

.. so; if you have those problems; get Solaris v7/v8 for Intel
(or if you can afford it-> sparc!) .. and run Zope of that.

I do so .. but then again; I am not near the 2gb barrier that
many people have come over. ;) 

.. on the other hand; I am not aware of the various "beta"
filesystem implementations and kernel "to-do"'s for linux, 
but I suspect that it will not be long before that problem
is solved.

.. oh! When I think of it.. SGI has ported their XFS to linux.
Not sure how far that implementation has gone yet.. but the
link to check out is;

	http://oss.sgi.com/projects/xfs/

Looks promising.. and a "production" like filesystem for linux
is a "must" as far as I can see. ;) Just read the brief here;

  Sub-second filesystem recovery after crashes or power
  failures (never wait for long fscks again)

  64-bit scalability: millions of terabytes, millions of files,
  and a million files per directory (no more 2 GB limits)

  High reliability and performance from journaling and other
  advanced algorithms

Hope that helped a bit??

.. just shoot if there's more I can help with! ;) 

-- 


Med vennlig hilsen,
Jørgen Skogstad


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