From Bugzilla Helper: User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.4) Gecko/20030624 Netscape/7.1 (ax) Description of problem: In the section detailing mount options for NFS filesystems, it says that the default value for rsize and wsize options is 4k. [quote] rsize=8192,wsize=8192 This will make your nfs connection faster than with the default buffer size of 4096. (NFSv2 does not work with larger values of rsize and wsize.) [/quote] This does not tie up with what the kernel source appears to be doing, which is to use the server specified default values. The performance turning pages at http://nfs.sourceforge.net/nfs-howto/performance.html also say that the default is typically server specified. [quote] If no rsize and wsize options are specified, the default varies by which version of NFS we are using. The most common default is 4K (4096 bytes), although for TCP-based mounts in 2.2 kernels, and for all mounts beginning with 2.4 kernels, the server specifies the default block size. [/quote] Version-Release number of selected component (if applicable): mount-2.11y-31.1 How reproducible: Always Steps to Reproduce: 1. man 'mount' 2. Search for 'rsize'/'wsize' 3. Expected Results: Documentation for default value of rsize/wsize options corresponds to actual practice in kernel source. Additional info: The man page should probably also warn about potential problems with an oversized rsize/wsize as the the above doc on nfs.sourceforge.net [quote] If the rsize/wsize is too large the symptoms are very odd and not 100% obvious. A typical symptom is incomplete file lists when doing ls, and no error messages, or reading files failing mysteriously with no error messages. [/quote]
Also, the mount(8) and nfs(5) man pages have conflicting statements about the default rsize,wsize values. Mount(8) says 4K; nfs(5) says 1K.
Fixed in util-linux-2.11y-31.12
This issue is on Red Hat Engineering's list of planned work items for the upcoming Red Hat Enterprise Linux 3.8 release. Engineering resources have been assigned and barring unforeseen circumstances, Red Hat intends to include this item in the 3.8 release.
An advisory has been issued which should help the problem described in this bug report. This report is therefore being closed with a resolution of ERRATA. For more information on the solution and/or where to find the updated files, please follow the link below. You may reopen this bug report if the solution does not work for you. http://rhn.redhat.com/errata/RHBA-2006-0456.html