On 18.04.2018 21:28, David Sterba wrote: > On Wed, Apr 18, 2018 at 06:14:07PM +0300, Nikolay Borisov wrote: >> >> >> On 18.04.2018 18:10, Brendan Hide wrote: >>> Hi, all >>> >>> I'm looking for some advice re compression with NVME. Compression helps >>> performance with a minor CPU hit - but is it still worth it with the far >>> higher throughputs offered by newer PCI and NVME-type SSDs? >>> >>> I've ordered a PCIe-to-M.2 adapter along with a 1TB 960 Evo drive for my >>> home desktop. I previously used compression on an older SATA-based Intel >>> 520 SSD, where compression made sense. >>> >>> However, the wisdom isn't so clear-cut if the SSD is potentially faster >>> than the compression algorithm with my CPU (aging i7 3770). >>> >>> Testing using a copy of the kernel source tarball in tmpfs it seems my >>> system can compress/decompress at about 670MB/s using zstd with 8 >>> threads. lzop isn't that far behind. But I'm not sure if the benchmark >>> I'm running is the same as how btrfs would be using it internally. >>> >>> Given these numbers I'm inclined to believe compression will make things >>> slower - but can't be sure without knowing if I'm testing correctly. >>> >>> What is the best practice with benchmarking and with NVME/PCI storage? >> >> btrfs doesn't support DAX so using it on NVME doesn't make much sense >> performance wise. > > Is'nt NVMe just "the faster SSD"? Not the persistent memory thing.
Indeed, brain fart on my part. NVDIMM is the persistent memory thing. > -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
