OSI MODEL

Basics of each layer in OSI model

Further details on each OSI model layer protocols/features

Implementation details OSI model

Various terminologies used for data transferred in each layer

 In which layer does Switch or Router exists?

What are basic performance metrics to look upon ?

Response time

Throughput

Latency

Scalability

CPU / network./ Disk utilization

What are the factors need to be considered while choosing a performance benchmark

There are many factors need to be consider based on application , few of them are below

• Is your workload I/O dependent?
• Will more CPUs help or hinder?
• Will adding more memory help?
• Do you need Fiber/SSD or will Copper/SATA/RAID do the trick?
• Do you need throughput or IOPS?
• Do you need horizontal scalability or will vertical work?

ZFS Logbias Property || Throughput vs Latency

In Oracle ZFS appliance there are two kind of disk HDD (Normal disk) and SSD (Faster I/O disk compared to HDD),
If In oracle public cloud volume is created with
logbias = throughput : data will be directly written to HDD synchronously.
logbias =latency: data will be first written to SSD (faster disk) and later will be moved to HDD in background .

Why do we need this setting and how it is useful 
SSD disk are costlier compared to HDD , therefore SSD can be used in such case where we need high throughput specially Write throughput . To optimizing cost/performance we need to have a setting to use both kind of disk