Dell EMC DEE-1111 Exam

The metrics that are recommended to start analyzing the overall efficiency of the array due to cache are array-level % Hit and % Cache WP. The array-level % Hit metric shows the percentage of read requests that are satisfied from the cache memory, without accessing the physical disks. A high % Hit value indicates that the cache is effective in reducing the read latency and improving the performance. The % Cache WP metric shows the percentage of cache memory that is occupied by write pending data, which is data that has been written to the cache but not yet destaged to the physical disks. A high % Cache WP value indicates that the cache is under pressure and may not have enough space to accommodate new write requests, which can lead to performance degradation. By monitoring these two metrics, a storage administrator can evaluate the overall efficiency of the array due to cache and identify any potential issues or bottlenecks.

System efficiency overview | Dell PowerMax: Data Reduction | Dell Technologies Info Hub

Metrics (PowerMax & VMAX) - VMware Docs

Dell EMC PowerMax storage

Replication cache | Dell EMC PowerMax and VMAX All Flash: TimeFinder SnapVX Local Replication

When expanding the capacity of a three-brick PowerMax 8000 running PowerMaxOS 5978.444.444 configured with Flash Drives RAID 5 (7+1) with SCM drives, the minimum supported configuration is 1x RAID 5 (7+1) added to each brick.This ensures that each brick has additional capacity and maintains the balance of storage across all bricks2.Reference:Dell EMC PowerMax Family Product Guide PowerMaxOS,Dell PowerMax Family Site Planning Guide PowerMax 2000 and PowerMax 8000,POWERMAX FAMILY PowerMax 2000 and 8000 - Dell Technologies Partner Portal

The metrics that are recommended to start analyzing the overall efficiency of the array due to cache are array-level % Hit and % Cache WP. The array-level % Hit metric shows the percentage of read requests that are satisfied from the cache memory, without accessing the physical disks. A high % Hit value indicates that the cache is effective in reducing the read latency and improving the performance. The % Cache WP metric shows the percentage of cache memory that is occupied by write pending data, which is data that has been written to the cache but not yet destaged to the physical disks. A high % Cache WP value indicates that the cache is under pressure and may not have enough space to accommodate new write requests, which can lead to performance degradation. By monitoring these two metrics, a storage administrator can evaluate the overall efficiency of the array due to cache and identify any potential issues or bottlenecks.

System efficiency overview | Dell PowerMax: Data Reduction | Dell Technologies Info Hub

Metrics (PowerMax & VMAX) - VMware Docs

Dell EMC PowerMax storage

Replication cache | Dell EMC PowerMax and VMAX All Flash: TimeFinder SnapVX Local Replication

If utilization increases by 10% for both systems A and B, where system A has a current utilization of 10% and system B has a current utilization of 70%, the response times for systems A and B would not necessarily increase linearly with utilization.The exact impact on response times would depend on various factors including workload characteristics, system configuration, and resource contention among others34. However, without specific details on these factors, it's not possible to provide an accurate prediction for the new response times.Reference:PowerMax and VMAX All Flash: Storage Resource Pool (SRP) Effective Used Capacity threshold alert,Service levels and eNAS | Dell EMC PowerMax and VMAX All Flash: eNAS Best Practices

While using DELL EMC Data Erasure on a PowerMax, the minimum number of overwrites needed to support compliance with internal policies and regulatory requirements is 3. The application has prompts and notifications.Such as the option to choose the number of Media Eraser 'wipes' (3x times, 5x times or 7x times)1.Reference:Dell EMC Community Network