latency Archives | n0derunner

Single threaded DB performance on Nutanix HCI

Published: May 27, 2022 (Updated: January 3, 2023) in Nutanix, fio, latency, windows, sqlserver, diskspd, aws, rds by gary. 1 Comment on Single threaded DB performance on Nutanix HCI.

tl;dr A Nutanix cluster can persist a replicated write across two nodes in around 250 uSec which is critical for single-threaded DB write workloads. The performance compares very well with hosted cloud database instances using the same class of processor (db.r5.4xlarge in the figure below). The metrics below are for SQL insert transactions not the […]

Impact of Paravirtual SCSI driver VS LSI Emulation with Data.

Published: March 30, 2015 (Updated: September 7, 2022) in Storage Performance, vmware, latency, scsi, virtualization by gary. Leave a Comment on Impact of Paravirtual SCSI driver VS LSI Emulation with Data..

TL;DR Comparison of Paravirtual SCSI Vs Emulated SCSI in with measurements. PVSCSI gives measurably better response times at high load. During a performance debugging session, I noticed that the response time on two of the SCSI devices was much higher than the others (Linux host under vmware ESX). The difference was unexpected since all the devices […]