Monitor Performance

Question 1

What are 4 notable causes of front end performance problems?

Answer 1

• Too much on the home page
• Large Images
• Large Javascript Libraries
• Too Many Fonts

Question 2

What is a cache?

Answer 2

A cache is a high-speed data storage layer which stores a subset of data.

Question 3

How does eTag caching improve performance

Answer 3

This option is used to determine the state of an API request on the server so if a subsequent request is made, it will return a status 304 (not modified) indicating that the data has not changed. This prevents the server from having to recalculate the data for the API request.

Question 4

What considerations does a developer need to take into account when using the cache manager?

Answer 4

• How frequently the cached data changes.
• How much data is stored in the cache (to prevent automatic cache eviction).
• How long the cache should live vs the cost of reloading.

Question 5

What is the shared (distributed) cache primarily used for?

Answer 5

Real time inventory and pricing.

Question 6

What are the layers of the shared (distributed) cache ?

Answer 6

Local (in memory on server) > shared cache (in sql or redis)

Question 7

True or False: Session state is used to store the InsiteCacheId. This InsiteCacheId GUID is then referenced in the cookie to retrieve the Shopping Cart.

Answer 7

False

Question 8

When locally monitoring db calls what is a good rule of thumb for how long a “suspicious” query takes?

Answer 8

300ms

Question 9

What are some strategies to help reduce table scans when using LINQ?

Answer 9

• Writing direct SQL queries (instead of LINQ)
• Creating a stored procedure.
• Creating a supporting table with the data you need

Question 10

What are two convience methods available to improve DB performance when using LINQ queries?

Answer 10

• GetTableAsNoTracking
• WhereContains

Question 11

Which Products API is used in the classic CMS?

Answer 11

Products V1 This is less performant because it leverages the search data less and is built with less efficient stored procs for gathering related product information.

Question 12

Name 3 changes that can improve the performance of products on the site?

Answer 12

1. Limit the number of entries in any given cross-sell/accessory/related product widget
2. Reduce the default page limit on product list pages
3. Keep the number of traits on product variants low (between 2-4)

Question 13

How are custom properties stored in the database?

Answer 13

Each one is represented in the database as a name/value pair

Question 14

Which entity is likely to have the greatest performance degregation from adding a custom property?

Answer 14

Product

For most entities, the system is not constantly reading different data so retrieving, say, 50 custom properties for a customer is likely not going to be a problem. Take those 50 properties to the Product or Category tables, for example, you will likely have some performance concerns.

Question 15

What are two approaches to add additional information to products without using custom properties (to avoid performance issues)?

Answer 15

• Alter the ProductCollection pipeline to only retrieve those properties you actually need
• Use a custom table for the product instead of custom properties

Question 16

How does the “Show Attributes On Search” affect performance?

Answer 16

The list of attribute facet checkboxes on a search results page can be extremely long which can result in slower front-end performance.

Question 17

Do inactive promotions affect performance?

Answer 17

No only active promotions are checked.

Question 18

True or False: Having the “Allow Multiple Promotions” set to “OFF” is recomended to imporve promotions performance?

Answer 18

False

This setting only applies to order promotions so it helps performance very little because all lines still must be checked.

Question 19

Would having 12 concurrent promotions present a significant performance obstacle?

Answer 19

No

Having 10 or 15 active promotions should not be an issue, but having several hundred would be aproblem.

Question 20

Does having multiple languages active impact performance?

Answer 20

Generally no.

It does not impact site performance, but has a large impact on elastic indexing as each language effectively has a seperate index.

Question 21

If the ERP requires a seperate API call for each product what can be done to minimize the performance hit?

Answer 21

Use a refresh job for the inventory and only use real time for pricing.

Question 22

True or False - The Products V2 API requires real time pricing and inventory for performance reasons?

Answer 22

True

Question 23

True or False - Disabling translations if you do not use them improves performance.

Answer 23

True

Question 24

True or False - Empty translation records have no impact on system performance?

Answer 24

False

f you have multiple languages and use the Generate Records option in the Admin Console, the system will create many empty records which can slow down the system.