Critical Memory Performance Metrics for DDR4 Systems: Page Hit Analysis
Page Hit and Miss is often a metric used to describe caching architectures. In this context a Hit is when the page was already open and the Read/Write transaction occurred. A Miss is when an Activate[1] had to occur just prior in order to open the ...
Critical Memory Performance Metrics for DDR4 Systems: Bus Mode Analysis
For DDR4 there are 11 different modes and these metrics are Rank based. These include the following: Reset, Idle, Active, Precharge Power Down, Active Power Down, Maximum Power Down Mode, Self-Refresh, DLL Disable, Write Leveling, MPR Mode (also ...
Critical Memory Performance Metrics for DDR4 Systems: Power Management
If you are Facebook and its 3 am on the East Coast of the United States you probably want to see your Servers in a low power state. This can save you money and make your server farms more ‘green’.
Critical Memory Performance Metrics for DDR4 Systems: Latency
There are two types of latency to consider when looking at the cycle by cycle transmission of data on the DDR4 Data Bus. The first is the time between the Read or Write command and the data associated with that command, refered to as CAS and CAS ...
Critical Memory Performance Metrics for DDR4 Systems: Data Bus Utilization Analysis
This is the heart of any Server memory subsystem performance measurement. How much data can be passed within a second. Data bus utilization's can be expressed as rates (MB per Sec) or as percentages indicating utilization (used cycles divided by ...
Critical Memory Performance Metrics for DDR4 Systems
Second only to the speed of the processor, memory subsystems design dominates a server’s performance. The three traditional metrics of Latency, Bandwidth and Power Management are no longer enough to categorize the performance of modern Server memory ...