The nfs_hist command shows e.g. the number of reads that get serviced with a specific response time:
v3 read: 4817066 (blocking requests) - millisecond units 0 1 2 3 4 5 6 7 4144583 475420 86036 25125 16078 11301 9468 6301
What is the exact range for e.g. "0"? I would expect it to be between 0 and 1 ms and not exactly 0 ms. Can someone confirm this?
And another question about the "lun hist" command. What is the difference between scsi_write and scsi_write_extended?
Yes, the range is between 0 and 1 and not exactly 0. Any number of requests that is between 0-7 msecs represents memory reads. In the histogram 8-15 is missing and it starts from 16 msecs. Any request seen under 16 msec column and above represents a disk read.
Bikash
-----Original Message----- From: Pascal Dukers [mailto:pascal.dukers@asml.com] Sent: Tuesday, April 08, 2008 9:56 AM To: toasters@mathworks.com Subject: "nfs_hist" and "lun hist" output questions
The nfs_hist command shows e.g. the number of reads that get serviced with a specific response time:
v3 read: 4817066 (blocking requests) - millisecond units 0 1 2 3 4 5 6 7 4144583 475420 86036 25125 16078 11301 9468 6301
What is the exact range for e.g. "0"? I would expect it to be between 0 and 1 ms and not exactly 0 ms. Can someone confirm this?
And another question about the "lun hist" command. What is the difference between scsi_write and scsi_write_extended? -- View this message in context: http://www.nabble.com/%22nfs_hist%22-and-%22lun-hist%22-output-questions -tp16565913p16565913.html Sent from the Network Appliance - Toasters mailing list archive at Nabble.com.
write and write_extended are just 2 different version of the SCSI write command, in the SCSI spec these are also called WRITE_6 and WRITE_10.
Write 10 has a 32 bit offset field vs. a 20 bit offset allowing access to larger devices. Some client OSs will use WRITE 6 for low block numbers and WRITE 10 for higher ones, others just use WRITE 10.
Britt, scsi geek.
On Tue, 8 Apr 2008, Pascal Dukers wrote:
The nfs_hist command shows e.g. the number of reads that get serviced with a specific response time:
v3 read: 4817066 (blocking requests) - millisecond units 0 1 2 3 4 5 6 7 4144583 475420 86036 25125 16078 11301 9468 6301
What is the exact range for e.g. "0"? I would expect it to be between 0 and 1 ms and not exactly 0 ms. Can someone confirm this?
And another question about the "lun hist" command. What is the difference between scsi_write and scsi_write_extended?
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Britt Bolen -
Choudhury, Bikash -
Pascal Dukers