looking to max out bandwidth of old 3Gb/s SAS JBOD

[bsdblue]

Hi all,
I just acquired a JBOD which was made in 2011, it has 60 2TB 7.2k SATA disks but using SATA-to-SAS adapters on each disk. There are two IO modules on the enclosure, each module offer 4 SFF-8088 ports, the speed of these SAS port is 3Gb/s. It were connected to a controller box equiped with 2 LSI SAS3160E HBA cards, running some kind of software raid. When connected the LSI HBA cards presents 120 disks to the controller(but actually only 60 disks, e.g. sdcc and sddj is the same disk). I have wiped out the software raid and managed to run zfs on it. If I run two sas cables from one HBA card to two IO modules, the write bandwidth is 1100MB/s. If I run two sas cables from two HBA cards to two IO modules, the write bandwidth is 1445MB/s.

Is it possible to max out the bandwith by using a somewhat newer controller box(used servers are so cheap anyway)? I'm looking at the DELL R620 1U box, equiped with a LSI SAS9207-8e HBA card. The R620 has PCIe-3.0 slots, and SAS 9207-8e is 6Gb/s, will I get better bandwidth?

suggestions appreciated. Thanks.

 

[HoneyBadger]

If the backplane in your JBOD is only capable of SAS 3.0Gbps, then a faster host card won't change that. Do you have an exact model on the JBOD?

If your SAS3160E or the server it's connected to was a bottleneck (which given its age is likely) then your speed will improve.

Welcome.

 

[bsdblue]

although the Jbod backplane is 3Gbps, the two IO modules together should be capable of doing 3Gbpsx4x2=24Gbps, right now it can only do 1445MB/s, there seems to be so space to improve. I read that the SAS1068E suffers from low performance issue, that's why I wonder newer server+newer HBA card can do better