Readynas 104, Avast AV, Malewarebytes. Yikes!

I have 4 drives in a Raid 5 config. I have been encountering very slow speeds with smaller files.  So, I conducted a test using a directory of 164 small files  totalling about 200KB [sic].    The tests just copies this directory from my NAS to a place on my SSD.  The target PC is a fast windows 10 machine. I wanted to see if Avast AV and Malwarebytes (MB) were effecting the time to copy the dir.  Here are some results:

1. AV and MB - about 90 seconds
2. AV and MB up but all real time protections turned off  - 67 seconds
3. AV, No MB (MB actually closed/exited) - 4.5 seconds
4. No AV (disabled),  No MB (closed) - 1.5 seconds
5. No AV (disabled)  and MB (all on) - 17 seconds 

So this tells us that

1. Without AV or MB (shut down completely) - the baseine speed is 1.5 seconds.
2. Just MB is 17 seconds, > 10x longer than the baseline - MB gives it the biggest hit and oddly that hit is mostly still there if its up but real time protections are disabled
3. Just AV is 4.5 seconds - 3x longer than baseline
4. MV+AV is 90 seconds - 20x longer than baseline. The speed is closer to a multiplicative effect of the MB and AV hits versus addative.

At this pont, I imagine a person reading this is thinkin, "Uh huh, what's that have to do with  a NAS?"  Here are the corresponding times copied from a local standard HD

1. AV and MB - about 0.3 seconds
2. not done
3. AV, No MB (MB actually closed/exited) - 0.17 seconds
4. No AV (disabled),  No MB (closed) - 0.17 seconds
5. No AV (disabled)  and MB (all on) - 0.3 seconds 

So when a local HD is the source ( the NAS isn't the source):

1. When AV and MB are on it's 300x faster than with the NAS - this is the big deal.
2. The effect of the AV is negligable (vs with the NAS it made the copy 3 times slower)
3. without either, the basline is 5x faster without the NAS (which, given the small file sizes might be OK relatively and probably not that big a deal in absolute times (an acceptable time waiting for tasks)

Obviously, I'll ping the MB and Avast but as I'm using free Avast that's unlikley plus this 3 product issue is a recipe for finger pointing.  MB is obviouly the bigger deal but why it's so lethal with AV when the NAS in particular is involved is the big bugaboo.  

EDIT

One more interesting item:

When I do a Properties on the copied directory on the SSD vs the NAS, they both report 200K for the files but the SSD rports 420KB actually occupied on disk while the NAS reports 10.2MB!  That's seems a bit much of a disparity.  These files are about 1K actual each which for the NAS comes out to be each 1K file taking about 64K (well, 62K) of disk space.