There is a great deal of discussion in this forum about the 'correct' way to apply L2ARC to a system to improve performance.
I think that what I am proposing may have value for others who fit my TrueNAS use case and am interested to see if I am off in the weeds.
1) My present system consists of a SuperMicro server with an 8-core/16-thread Intel CPU, 128 GB DDR and 2*12 TB Seagate Iron Wolf NAS drives as a mirrored pair running under TrueNAS Core 13.
2) My server is for personal home use - a mixture of movies, photo archives, ISO installers and full drive images for all my machines.
3) The 8 or so TB of useful space in my main pool is split roughly into two roughly 4 TB groups:
a) movies I almost never watch, drive images I hope I'll never need, photos I took years ago which I rarely access, and other old stuff I'm just not ready to get rid of yet, and
b) other stuff needed by me and my family on a daily, weekly and monthly basis.
4) I would like to convert the entire system to SSD, but 24 TB of SSDs is a bit out of my price range.
So - What do do?. It occurs to me they for a couple hundred bucks, I could add a fast 4 TB SSD as L2ARC. After about a month of cache warmup, I would expect that everything I regularly need would wind up in L2ARC and my normal performance would be at best, governed by ARC, and at worst governed by my SSD's speed.
Hence, for the most part, my system would perform as if I had spent many thousands of $ to get 24 TB of SSDs, and a much larger chassis to hold them all.
I would covet other people's thoughts on:
a) Are there flaws in my reasoning, and
b) Would I need to do some tweaking of tunables to make this perform as expected.
Thanks in advance. The amount of knowledge in the minds of those here humbles me.
I think that what I am proposing may have value for others who fit my TrueNAS use case and am interested to see if I am off in the weeds.
1) My present system consists of a SuperMicro server with an 8-core/16-thread Intel CPU, 128 GB DDR and 2*12 TB Seagate Iron Wolf NAS drives as a mirrored pair running under TrueNAS Core 13.
2) My server is for personal home use - a mixture of movies, photo archives, ISO installers and full drive images for all my machines.
3) The 8 or so TB of useful space in my main pool is split roughly into two roughly 4 TB groups:
a) movies I almost never watch, drive images I hope I'll never need, photos I took years ago which I rarely access, and other old stuff I'm just not ready to get rid of yet, and
b) other stuff needed by me and my family on a daily, weekly and monthly basis.
4) I would like to convert the entire system to SSD, but 24 TB of SSDs is a bit out of my price range.
So - What do do?. It occurs to me they for a couple hundred bucks, I could add a fast 4 TB SSD as L2ARC. After about a month of cache warmup, I would expect that everything I regularly need would wind up in L2ARC and my normal performance would be at best, governed by ARC, and at worst governed by my SSD's speed.
Hence, for the most part, my system would perform as if I had spent many thousands of $ to get 24 TB of SSDs, and a much larger chassis to hold them all.
I would covet other people's thoughts on:
a) Are there flaws in my reasoning, and
b) Would I need to do some tweaking of tunables to make this perform as expected.
Thanks in advance. The amount of knowledge in the minds of those here humbles me.
