Subject: Re: NetBSD/ofppc boots multiuser on Pegasos - msg#00051

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Re: NetBSD/ofppc boots multiuser on Pegasos

=?ISO-8859-1?Q?Jorge_Acereda_Maci=E1?= wrote: > Simon Burge wrote: > > =?ISO-8859-1?Q?Jorge_Acereda_Maci=E1?= wrote: > > > > > >>I finally got NetBSD/ofppc to boot multiuser via NFS on a Pegasos II > >>motherboard. NFS reads are ok, but writes are broken (I suspect of a > >>firmware bug, something to do with packet size, but have to verify it). > > > > > > Does > > > > options NFS_BOOT_RWSIZE=1024 > > > > help? This can help tremendously when your ethernet driver and/or > > hardware isn't up to scratch where all the UDP retries on reads or > > writes kill NFS. > > Indeed. It helps to the point that without that option it doesn't even > mount root :-) Heh :) > Maybe you have a theory on what's going on. When I copy a file, what I > get on the NFS server is a file of the same size, but with chunks of > zeros interleaved, that is: > > 0x0000 <correct data> > 0x1000 <zeros> > 0x2000 <correct data> > 0x3000 <zeros> > ... No ideas offhand. That's a page size which may or may not mean anything. I wonder what happens if you do something like: dd if=/netbsd of=/tmp/foo bs=4k count=1 seek=1 do you zeros or real data at 0x1000 in /tmp/foo ? Still, I'm not sure what that proves either if it works or not... Simon.

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Re: NetBSD/ofppc boots multiuser on Pegasos

=?ISO-8859-1?Q?Jorge_Acereda_Maci=E1?= wrote: > Simon Burge wrote: > > > No ideas offhand. That's a page size which may or may not mean > > anything. > > > > I wonder what happens if you do something like: > > > > dd if=/netbsd of=/tmp/foo bs=4k count=1 seek=1 > > > > do you zeros or real data at 0x1000 in /tmp/foo ? Still, I'm not > > sure what that proves either if it works or not... > > > > Interesting. I got two identical chunks at 0x0000 and 0x1000 which are > in fact the data at 0x0000 in /netbsd. > > Want to hear something really annoying? if I use dd if=/netbsd > of=/tmp/foo instead of cp, I get an exact replica. I think cp uses mmap instead of read, but still uses writes normally? Maybe try regress/sys/uvm/mmap ? Simon.

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Re: NetBSD/ofppc boots multiuser on Pegasos

=?ISO-8859-1?Q?Jorge_Acereda_Maci=E1?= wrote: > Simon Burge wrote: > > =?ISO-8859-1?Q?Jorge_Acereda_Maci=E1?= wrote: > > > > > >>I finally got NetBSD/ofppc to boot multiuser via NFS on a Pegasos II > >>motherboard. NFS reads are ok, but writes are broken (I suspect of a > >>firmware bug, something to do with packet size, but have to verify it). > > > > > > Does > > > > options NFS_BOOT_RWSIZE=1024 > > > > help? This can help tremendously when your ethernet driver and/or > > hardware isn't up to scratch where all the UDP retries on reads or > > writes kill NFS. > > Indeed. It helps to the point that without that option it doesn't even > mount root :-) Heh :) > Maybe you have a theory on what's going on. When I copy a file, what I > get on the NFS server is a file of the same size, but with chunks of > zeros interleaved, that is: > > 0x0000 <correct data> > 0x1000 <zeros> > 0x2000 <correct data> > 0x3000 <zeros> > ... No ideas offhand. That's a page size which may or may not mean anything. I wonder what happens if you do something like: dd if=/netbsd of=/tmp/foo bs=4k count=1 seek=1 do you zeros or real data at 0x1000 in /tmp/foo ? Still, I'm not sure what that proves either if it works or not... Simon.

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Re: NetBSD/ofppc boots multiuser on Pegasos

=?ISO-8859-1?Q?Jorge_Acereda_Maci=E1?= wrote: > Simon Burge wrote: > > > No ideas offhand. That's a page size which may or may not mean > > anything. > > > > I wonder what happens if you do something like: > > > > dd if=/netbsd of=/tmp/foo bs=4k count=1 seek=1 > > > > do you zeros or real data at 0x1000 in /tmp/foo ? Still, I'm not > > sure what that proves either if it works or not... > > > > Interesting. I got two identical chunks at 0x0000 and 0x1000 which are > in fact the data at 0x0000 in /netbsd. > > Want to hear something really annoying? if I use dd if=/netbsd > of=/tmp/foo instead of cp, I get an exact replica. I think cp uses mmap instead of read, but still uses writes normally? Maybe try regress/sys/uvm/mmap ? Simon.