My experience is that an IR HBA with FBWC and supercap can somewhat accelerate latency with slow media. Wrapping each drive in a VD to enable WB caching, though, is extra work and confounds drive metrics.
It’s also been that cache modules / BBUs can be flaky, and these things really need additional monitoring (hint: iDRAC isn’t enough) If you don’t already have optional cache / BBU aka CV, I wouldn’t spend the $ retrofitting, especially on systems from 6-7 years ago. Put the $ toward faster networking or NVMe-enabled systems. The R640 / R740 can be had in all-NVMe chassis and is an inexpensive way to break out of the SAS/SATA trap. There are no fewer than 40 R740 chassis types, if you count risers. This document https://dl.dell.com/manuals/common/dellemc-nvme-io-topologies-poweredge.pdf gives you a taste. Assuming that these are H330mini or similar, and all SAS/SATA, I personally would set the HBA mode / personality to JBOD / passthrough / HBA and act like the RoC isn’t there. Including boot drives if you don’t have BOSS. ymmv. Whatever you do, I advise using DSU to update firmware. Old firmware on these LSI / PERC / Avago / Broadcom HBAs can present significant issues. > On May 18, 2025, at 8:11 AM, Anthony Fecarotta <anth...@linehaul.ai> wrote: > > Does running a RAID controller in HBA mode (not to be confused with IT mode) > impact Ceph performance compared to using a dedicated HBA card? Is there any > documentation or benchmarking data showing improved performance with true HBA > hardware? > > For what it's worth my cluster is on Dell PowerEdge R740 machines. > > Thank you for your insights. > > > Regards, > [image] > Anthony Fecarotta > Founder & President > [image] anth...@linehaul.ai <mailto:anth...@linehaul.ai> > [image] 224-339-1182 [image] (855) 625-0300 > [image] 1 Mid America Plz Flr 3 Oakbrook Terrace, IL 60181 > [image] www.linehaul.ai <http://www.linehaul.ai/> > [image] <http://www.linehaul.ai/> > [image] <https://www.linkedin.com/in/anthony-fec/> > _______________________________________________ > ceph-users mailing list -- ceph-users@ceph.io > To unsubscribe send an email to ceph-users-le...@ceph.io _______________________________________________ ceph-users mailing list -- ceph-users@ceph.io To unsubscribe send an email to ceph-users-le...@ceph.io
