In-Memory Cache for Web Application Data

• US 20170116135A1
• Filed: 10/26/2015
• Published: 04/27/2017
• Est. Priority Date: 10/26/2015
• Status: Active Grant

• Current Assignee: Salesforce.com, Inc.
• Original Assignee: Salesforce.com, Inc.
• Inventors: Sundaravaradan, Barathkumar, Wall, Christopher James, Lopez, Lawrence Thomas, Sydell, Paul, Duvur, Sreeram, Devadhar, Vijayanth
• Granted Patent: US 10,013,501 B2
• Time in Patent Office: Days
• CPC Class Codes: G06F 12/0806 Multiuser, multiprocessor or multiprocessing cache systems
• CPC Class Codes: G06F 12/084 with a shared cache
• CPC Class Codes: G06F 12/0842 for multiprocessing or multitasking
• CPC Class Codes: G06F 12/0848 Partitioned cache, e.g. separate instruction and operand caches
• CPC Class Codes: G06F 16/9574 of access to content, e.g. by caching
• CPC Class Codes: G06F 2212/282 Partitioned cache
• CPC Class Codes: G06F 2212/283 Plural cache memories
• CPC Class Codes: G06F 2212/62 Details of cache specific to multiprocessor cache arrangements

Abstract

Techniques are disclosed relating to caching web application data. In some embodiments, a computing system maintains a multi-tenant database and an in-memory cache for the database. In some embodiments, the computing system is configured to store data in an entry in response to a store request and retrieve data in response to a read request. In various embodiments, data cached by one tenant is not visible to other tenants. The cache may be partitioned and each partition may have an assigned capacity. The computing system may be configured to evict cached data based on capacity thresholds, least-recently-used information, time-to-live information, amount of data in an entry, etc. The cache may indicate misses when requested data is not present. Various disclosed techniques may improve web application performance while maintaining privacy between tenants.

Claims

1. A method, comprising:

maintaining, by a computing system, a multi-tenant database that stores data generated by a plurality of web applications corresponding to different tenants;

maintaining, by the computing system, an in-memory cache for the database;

storing, by the computing system, data in an entry of the cache, wherein the storing is performed in response to a store request that includes the data and an identifier for the entry;

retrieving, by the computing system, data from the entry of the cache and not from the multi-tenant database, wherein the retrieving is performed in response to a read request that specifies the identifier; and

providing, by the computing system, the retrieved data to a requesting computing device from the cache.

2. The method of claim 1, wherein the storing is performed using a field of a shared cache data structure that stores entries for multiple different tenants.

3. The method of claim 1, wherein the in-memory cache is divided into a plurality of partitions, wherein one or more of the partitions are defined by a tenant, and wherein each of the partitions has a capacity threshold, the method further comprising:

monitoring used capacity of the partitions; and

evicting data from an entry in one of the partitions based on the monitoring.

4. The method of claim 3, wherein the evicting is further based on at least one of:

least-recently-used (LRU) information maintained for the entry;

time-to-live information maintained for the entry;

or

a size of data used by the entry.

5. The method of claim 1, further comprising:

determining a tenant corresponding to a user who initiated the store request; and

allowing only users associated with the tenant to access the data stored in the cache for the tenant.

6. The method of claim 1, wherein the in-memory cache is a session cache instance that is initiated for a user session and is not maintained after an end of the user session.

7. The method of claim 1, wherein the in-memory cache is an organization cache configured to store data for multiple different user sessions.

8. The method of claim 1, further comprising:

determining that the in-memory cache does not have data stored corresponding to an identifier specified by a request to retrieve data from the in-memory cache; and

transmitting a response to the request that indicates a cache miss.

9. A non-transitory computer-readable medium having instructions stored thereon that are executable by a computing device to perform operations comprising:

maintaining a multi-tenant database that stores data generated by a plurality of web applications corresponding to different tenants;

maintaining an in-memory cache for the database;

storing data in an entry of the cache in response to a store request that includes the data and an identifier for the entry;

retrieving data from the entry of the cache and not from the multi-tenant database in response to a read request that specifies the identifier; and

providing the data to a requesting computing device from the cache.

10. The non-transitory computer-readable medium of claim 9, wherein the storing is performed using a cache memory space that includes entries for a plurality of different tenants.

11. The non-transitory computer-readable medium of claim 9, wherein the in-memory cache is distributed across multiple servers.

12. The non-transitory computer-readable medium of claim 9, wherein the in-memory cache is divided into a plurality of partitions, wherein each of the partitions has a capacity threshold, and wherein the operations further comprise:

monitoring used capacity of the partitions; and

evicting data from an entry in one of the partitions based on the monitoring and at least one of the capacity thresholds.

13. The non-transitory computer-readable medium of claim 12, wherein the evicted entry is selected based on two or more of:

least-recently-used (LRU) information maintained for the entry;

time-to-live information maintained for the entry;

or

a size of data used by the entry.

14. The non-transitory computer-readable medium of claim 12, wherein the operations further comprise:

adjusting one of the capacity thresholds for a partition based on a payment from a tenant.

15. The non-transitory computer-readable medium of claim 9, wherein the operations further comprise:

storing information identifying a tenant corresponding to a user who initiated the store request; and

allowing only users associated with the tenant to access the data stored in the cache for the tenant.

16. The non-transitory computer-readable medium of claim 9, wherein the in-memory cache is a session cache instance that is initiated for a user session and is only accessible within the user session.

17. The non-transitory computer-readable medium of claim 9, wherein the in-memory cache is an organization cache configured to store data for multiple different user sessions.

18. The non-transitory computer-readable medium of claim 9, wherein the in-memory cache is allocated by a provider entity that provides an application for use by a subscriber entity, wherein the in-memory cache is used to store data generated by the application by the subscriber entity.

19. A non-transitory computer-readable medium having instructions stored thereon that are executable by a computing device to perform operations comprising:

generating, by a computing device, web application data;

transmitting a request to store the web application data in an in-memory cache maintained by one or more application servers, wherein the one or more application servers are also configured to maintain a database for one or more web applications executed by the computing device;

transmitting a request to retrieve the web application data from the in-memory cache; and

receiving retrieved data from the in-memory cache in response to the request, wherein the data is retrieved without accessing the database.

20. The non-transitory computer-readable medium of claim 19, wherein the request specifies an identifier of an entry in the in-memory cache.