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Alexander Puchmayr schrieb: |
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> Am Mittwoch 03 Juni 2009 schrieb Florian Philipp: |
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>> Do you have a spare network adapter, maybe an older 100MBit PCI card? |
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>> Maybe we should rule out a hardware fault on your ethernet chipset first. |
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>> |
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> I already thought on this, but the results of my tests dont indicate a |
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> hardware fault on the ethernet chipset, because: |
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> |
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> * I can run a ping -f to the machine, it runs for hours without the |
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> slightest problem |
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> * As long as files transfered are small enough (i.e. they fit in the cache |
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> buffer on the server) and the server has enough time to write back it to |
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> the disk, there is no problem |
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> * If I explicitly force the ethernet link to be 100FD instead of gigabit, |
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> the is also no problem. So I don't expect any error using another 100MBit |
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> card. |
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I would cross-check that anyway just to be sure. Other nic, other |
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kernel-module ... etc |
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> For me it looks like as if the following is happening: |
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> |
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> * Memory gets filled up with cached files, no problem so far |
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> * If no more physical ram is available, the system tries to free some memory |
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> internally, e.g. by flushing the caches. |
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> * If releasing cache entries and writing back data to their respective |
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> files does not perform fast enough, an internal memory allocation may not |
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> succeed, and I see the "page allocation failure" messages, with different |
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> processes/kernel threads in the first line. |
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> * I assume that most of the internal kernel threads don't get a problem in |
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> this situation, but there may be some critical parts where we do. Hence, it |
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> might just be a matter of probability whether it encounters such a critical |
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> part, and the probabilty increases with the MB/s the data is put to the NFS |
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> server. |
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errm, I dunno ... but how would then smaller and slower nfs-servers run |
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fine? Sounds unlikely to me. |
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Any special network-settings used? buffer-sizes, MTU, jumbo frames? |
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switch problems (you seem to have tried auto-negotiation off already). |
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Stefan |
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