The SATA S3700 series has been the de-facto for journals for some time. And journals don’t neeed all that much space. We’re using 400GB P3700’s. I’ll say a couple of things: o Update to the latest firmware available when you get your drives, qual it and stick with it for a while so you have a uniform experience o Run a recent kernel with a recent nvme.ko, eg. the RHEL 7.1 3.10.0-229.4.2 kernel’s bundled nvme.ko has a rare timing issue that causes us resets at times. YMMV. Which OS do you run? Read through this document or a newer version thereof https://www-ssl.intel.com/content/dam/www/public/us/en/documents/product-specifications/ssd-dc-p3700-spec.pdf or for SATA drives http://www.intel.com/content/www/us/en/solid-state-drives/ssd-dc-s3710-spec.html It’s possible that your vendor is uninformed or lying, trying to upsell you. At times larger units can perform better due to internal parallelism, ie. a 1.6TB unit may electrically be 4x 400GB parts in parallel. For 7200RPM LFF drives, as Nick noted 12x journals per P3700 is probably as high as you want to go, otherwise you can bottleneck. What *is* true is the distinction among series. Check the graph halfway down this page: http://www.anandtech.com/show/8104/intel-ssd-dc-p3700-review-the-pcie-ssd-transition-begins-with-nvme Prima fascia the P3500’s can seem like a relative bargain, but attend to the durability — that is where the P3600 and P3700 differ dramatically. For some the P3600 may be durable enough, given certain workloads and expected years of service. I tend to be paranoid and lobbied for us to err on the side of caution with the P3700. YMMV. — Anthony _______________________________________________ ceph-users mailing list ceph-users@xxxxxxxxxxxxxx http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
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