Virus Scanner under 6.6.0 kills performance

First off, let me thank you for your terrific help and assistance in this matter.

I run only OSX and Linux systems, so I could not use the testing tool you recommended, so I came up with my own battery of tests.

RN102 Tests

Network Configuration

Mac Mini, Model Macmini5,1, OSX  10.12

1 GB Adapter Configured and Confirmed

Apple Time Capsule, Model MB277LL/A, Firmware 7.6.7 (76700.5)

1 GB Switch Configured and Confirmed

NAS, Model RN10200, Firmware 6.6.0

1 GB Adapter Configured and Confirmed

MTU 1500 across all

RN102 Configured with 1 4 TB Volume (2x4TB Hitachi Drives, RAID 1)

Volume Broken across 6 shares

Snapshots enabled (schedule varying by volatility of share)

1.83 TB free of 3.63 TB usable

Data1.23 TB

Snapshots584.63 GB

SMART Status on both disks checked, no errors reported

Virus Scanner Update Status:

Mounted Share “Backups” via AFP under mount point:

//user@NAS%20%28AFP%29._afpovertcp._tcp.local/Backups

Tested using openSUSE-13.2-DVD-x86_64.iso (4.68GB, 4,678,746,112 bytes on disk)

Virus Scanner OFF Results

UPLOAD

1.  4678746112 100%   26.31MB/s    0:02:49

2.  4678746112 100%   29.13MB/s    0:02:33

3.  4678746112 100%   27.02MB/s    0:02:45

4.  4678746112 100%   23.43MB/s    0:03:10

AVG     26.475 MB/s

DOWNLOAD

1.  4678746112 100%   40.19MB/s    0:01:51

2.  4678746112 100%   42.08MB/s    0:01:46

3.  4678746112 100%   42.82MB/s    0:01:44

4.  4678746112 100%   42.42MB/s    0:01:45

Avg     41.8775 MB/s

Virus Scanner ON Results

UPLOAD

1.  4678746112 100%   27.50MB/s    0:02:42

2.    4678746112 100%   28.23MB/s    0:02:38

3.  4678746112 100%   28.31MB/s    0:02:37

4.  4678746112 100%   24.85MB/s    0:02:59

Avg     27.2225 MB/s

DOWNLOAD

1.  4678746112 100%   39.10MB/s    0:01:54

2.  4678746112 100%   42.11MB/s    0:01:45

3.  4678746112 100%   42.44MB/s    0:01:45

4.  4678746112 100%   40.12MB/s    0:01:51

Avg     49.9425 MB/s

This is DEFINITELY NOT the behavior and throughput I saw earlier, so I did another set of tests after a restart of the RN to test a theory I had.  I noted when the NAS started back up the disks were “being hammered” for about 4-5 minutes post start up, so I waited for that thrashing to stop before starting tests.

Note:  After the reboot, the virus definition file was updated:

Virus Scanner ON Results

UPLOAD 

1.  4678746112 100%   24.75MB/s    0:03:00

2.  4678746112 100%   24.88MB/s    0:02:59

3.  4678746112 100%   26.27MB/s    0:02:49

4.  4678746112 100%   24.61MB/s    0:03:01

Avg     25.1275 MB/s

Note: Speed in transfers varied from 30MB/s to 11MB/s as I watched progress, chaotically.

Over the course of the three minute runs, this shows the variance of the RN throughput over a time period

DOWNLOAD

1.  4678746112 100%   41.06MB/s    0:01:48

2.  4678746112 100%   41.34MB/s    0:01:47

3.  4678746112 100%   40.03MB/s    0:01:51

4.  4678746112 100%   41.99MB/s    0:01:46

Avg      41.104 MB/s

Note: Speed in transfers varied from 49MB/s to 29MB/s as I watched progress, chaotically.

Over the course of the three minute runs, this shows the variance of the RN throughput over a time period

Virus Scanner OFF Results

UPLOAD

1.  4678746112 100%   25.84MB/s    0:02:52

2.  4678746112 100%   27.73MB/s    0:02:40

3.  4678746112 100%   25.72MB/s    0:02:53

4.  4678746112 100%   26.13MB/s    0:02:50

Avg      26.355 MB/s

Note:  Speed in transfers varied from 28MB/s to 24MB/s  While this is a variance, this is a “smaller gap” than observed when the scanner was active.

DOWNLOAD

1.  4678746112 100%   41.45MB/s    0:01:47

2.  4678746112 100%   41.89MB/s    0:01:46

3.  4678746112 100%   41.32MB/s    0:01:47

4.  4678746112 100%   41.63MB/s    0:01:47

Avg      41.5725 MB/s

I also decided to run a few FTP tests, to see if the behavior was somehow isolated to the AFP sharing.

FTP

UPLOAD

1.  4678746112 bytes sent in 02:24 (30.84 MiB/s)

2.  4678746112 bytes sent in 03:09 (23.59 MiB/s)

3.  4678746112 bytes sent in 03:44 (19.85 MiB/s)

4.  4678746112 bytes sent in 03:31 (21.08 MiB/s)

Avg    23.84 MiB/s

DOWNLOAD

1.  4678746112 bytes received in 01:43 (43.07 MiB/s)

2.  4678746112 bytes received in 01:38 (45.22 MiB/s)

3.  4678746112 bytes received in 01:41 (44.01 MiB/s)

4.  4678746112 bytes received in 01:36 (46.47 MiB/s)

Avg   44.6925 MiB/s

A note of interest with respect to the FTP testing, I was watching the FTP rate of transfer, and saw it slowly decrease from a high starting value, decreasing by roughly .02 MB/s every 3-5 seconds over the duration of the transfers, until reaching the lowest throughput value in the last few seconds of the transfer.  The final average speed of the transfer, as pasted above, is roughly the median of the transfer speed range.  As an example, on the 4th trial the transfer speed at start was 48 MB/s and would down to 46.02 MB/s near the end, arriving at the average speed of 46,47 MiB/s

This behavior was consistent on both download and upload tests.

Intermediate Summary:

Although I cannot reproduce the abhorrent behavior I saw earlier today with singular file transfers, I have satisfied myself that this unit was acting incredibly poorly under load when I was transferring 100+ GB to 1TB of data earlier, and that performance was significantly improved by disabling the virus scanning as reported earlier.

During these tests, I have confirmed that after a restart the virus scanner enabled can impact performance as a roughly 300% throughput variance on a “idle” file type (not an EXE or ZIP that would actively incur the virus scanning) was seen only after restart before the virus scanner was disabled.

Additionally, ever since I set this unit up in May, I have had the RN under load “lock up” AFP sharing, and need to be restarted to restore service.  This affects all shares, and the RN exhibits this same behavior when shared over LAN or WiFi.

I also note that I got much lower results than your SMB testing, and that the variance of up to down for me is almost a 62% delta, whereas for your testing is was roughly only a 5% variance.

Conclusion:

The above indicates to me that the ReadyNAS may not be the best choice for a “non Windows” environment, and the revelation that the “Virus Scanning bug” has potentially returned to the software as a regression speaks to the quality of development.