topic Re: Is it bits or bytes (Performance Advisor)? in ONTAP Discussions

Is it bits or bytes (Performance Advisor)?

mike_burris — Thu, 05 Jun 2025 07:09:00 GMT

I've read through documentation (which isnt great btw) and can't seem to find an answer. I just called support and the gentleman I spoke with, although nice, admitted that he had no idea. So does anyone know, are the 'kb_per_sec' and 'mb_per_sec' vertical axis' on the graphs bits or bytes? Makes a huge difference as one would guess..

Thanks in advance!

Re: Is it bits or bytes (Performance Advisor)?

scottgelb — Sun, 12 Sep 2010 01:18:43 GMT

Has to be bytes. The stats output is also not documented so well, but the KB listed in the description is definitely kilobytes for the unit kb_per_sec (stats counter below).

Name: disk_data_read
Description: Disk KB read per second
Properties: rate
Unit: kb_per_sec

Even more confusing...and I hope this is a typo.. the advisor.pdf guide gives vfiler read/write in bytes for the object, but the description states kilobytes (below from advisor.pdf v4.0)

vfiler_read_bytes Data read in kilobytes per second on the vFiler unit
vfiler_write_bytes Data written in kilobytes per second on the vFiler unit

Re: Is it bits or bytes (Performance Advisor)?

eric_barlier — Mon, 13 Sep 2010 03:36:10 GMT

It would be nice if the "storage" way of doing bits and bytes was aligned with the networking world where:

B: Bytes

b: bits

8 bits = 1 byte (B)
1024 bytes = 1 Kilobyte (KB)
1024 Kilobytes = 1 Megabyte (MB)

Name: disk_data_read
Description: Disk KB read per second > capital KB infers bytes?
Properties: rate
Unit: kb_per_sec > small letter kb infers bits if compared to networking standards?

The explanation above could be correct still, but Im not sure due to the way networking deals with this. It seems logical for me to differentiate the way networking does it.

Eric

Re: Is it bits or bytes (Performance Advisor)?

adaikkap — Mon, 13 Sep 2010 04:00:41 GMT

Its bytes.And not bits.

Regards

adai

Re: Is it bits or bytes (Performance Advisor)?

scottgelb — Mon, 13 Sep 2010 04:49:03 GMT

Amen... I wish the docs were more consistent and fit networking... NetApp did a good job on this with the former Netcache product where Kb was bits but the ONTAP documentation is confusing in some cases. But when in doubt, it's bytes.

Re: Is it bits or bytes (Performance Advisor)?

scottgelb — Mon, 13 Sep 2010 04:50:07 GMT

Adai - thank you for clarifying...can you also address the vfiler example I pasted above? The value for bytes has a description of kilobytes... is this a typo or bytes really means kilobytes for these vfiler read/write fields?