RFC 5663, "Parallel NFS (pNFS) Block/Volume Layout", January 2010

Note: This RFC has been updated by RFC 6688

Errata ID: 4139
Status: Verified
Type: Technical
Publication Format(s) : TEXT
Reported By: Christoph Hellwig
Date Reported: 2014-10-23
Verifier Name: Martin Stiemerling
Date Verified: 2016-02-02

Section 2.7 says:

<section doesn't exist yet>

It should say:

2.7.  Volatile write caches

   Many storage devices implement volatile write caches that require an
   explicit flush to persist the data from write write operations to
   stable storage.  When a volatile write cache is used the pNFS server
   must ensure the volatile write cache has been committed to stable
   storage before the LAYOUTCOMMIT operation returns.  An example for
   this behavior are SCSI devices with the WCE (Writeback Cache Enable)
   bit set to 1 in the caching mode page (mode page 0x8),
   which require a "SYNCRONIZE CACHE (10)" or "SYNCRONIZE CACHE (16)"
   operation to write back the storage device cache.

Notes:

RFC5663 currently doesn't acknowledge the existence of volatile write caches, but they are common in consumer or SMB storage systems. Add a section that requires the server to take care of them.

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