System having in-memory buffer service, temporary events file storage system and events file uploader service

• US 9,632,849 B2
• Filed: 12/21/2015
• Issued: 04/25/2017
• Est. Priority Date: 09/15/2015
• Status: Active Grant

• Current Assignee: Salesforce.com, Inc.
• Original Assignee: Salesforce.com, Inc.
• Inventors: Pradeep, Aakash, Torman, Adam, Warshavsky, Alex, Jain, Samarpan
• Primary Examiner(s): DORAIS, CRAIG C
• Application Number:
  US14/976,115
• Publication Number:
  US 20170075735A1
• Time in Patent Office: 491 Days
• Field of Search: None
• CPC Class Codes: G06F 16/13 File access structures, e.g. distributed indices arrangements of input from, or output to, record carriers G06F3/06
• CPC Class Codes: G06F 16/16 File or folder operations, e.g. details of user interfaces specifically adapted to file systems
• CPC Class Codes: G06F 16/183 Provision of network file services by network file servers, e.g. by using NFS, CIFS network file access protocols H04L67/1097
• CPC Class Codes: G06F 16/955 using information identifiers, e.g. uniform resource locators [URL]
• CPC Class Codes: G06F 3/061 Improving I/O performance
• CPC Class Codes: G06F 3/0619 in relation to data integrity, e.g. data losses, bit errors
• CPC Class Codes: G06F 3/0643 Management of files
• CPC Class Codes: G06F 3/0656 Data buffering arrangements
• CPC Class Codes: G06F 3/067 Distributed or networked storage systems, e.g. storage area networks [SAN], network attached storage [NAS]
• CPC Class Codes: G06F 9/542 Event management; Broadcasting; Multicasting; Notifications
• CPC Class Codes: H04L 47/50 Queue scheduling
• CPC Class Codes: H04L 67/01 Protocols
• CPC Class Codes: H04L 67/06 specially adapted for file transfer, e.g. file transfer protocol [FTP]
• CPC Class Codes: H04L 67/1004 Server selection for load balancing
• CPC Class Codes: H04L 67/568 Storing data temporarily at an intermediate stage, e.g. caching

Abstract

Computer-implemented methods and systems are provided for writing events to a data store. An application server generates events, the data store that stores the events, and a temporary events file storage system (TEFSS) temporarily stores groups of events as events files. When events are unable to be written directly to the data store, an indirect events writer is invoked that includes event capture threads each being configured to generate a particular events file, and write it to the TEFSS. Each events file includes a plurality of events flushed from an in-memory buffer service. An events file uploader service reads the events file(s) from the TEFSS, and then writes the events from each of the events files to the data store.

Claims

1. A system, comprising:

a data store that is configured to store events;

an application server configured to run a client application that generates the events, wherein the application server comprises;

an in-memory buffer service;

a capture service configured to;

receive events generated by the client application running on the application server and to provide the events to the in-memory buffer service, wherein the in-memory buffer service is configured to temporarily hold the events in a bounded buffer that is implemented in physical memory at the application server, wherein the bounded buffer comprises a plurality of single-threaded buffer segments that are each configured to temporarily hold some of the events received from the capture service until a flush operation is performed, wherein each particular single-threaded buffer segment holds a plurality of events;

a consumer executor service configured to;

instantiate a plurality of consumer threads that each correspond to a particular single-threaded buffer segment, wherein each consumer thread comprises;

an instance of an events reader that is configured to read events flushed from a corresponding single-threaded buffer segment and to add an identifier to each the events; and

an instance of a direct events writer that is configured to attempt to directly write each event to the data store;

a temporary events file storage system (TEFSS);

wherein the application server comprises;

an indirect events writer that is invoked when the events are unable to be directly written to the data store, comprising;

a plurality of event capture threads each being configured to;

generate a particular events file that includes a plurality of events flushed from an in-memory buffer service, and write that particular events file to the TEFSS; and

an events file uploader service that is configured to read at least one events file from the TEFSS, and then write the events from each of the retrieved events files to the data store.

2. The system according to claim 1, wherein each consumer thread provides the events to a corresponding one of the event capture threads, and wherein each of the event capture threads comprises:

an instance of an events file writer; and

an instance of an invoker that is configured to;

determine whether a corresponding instance of the direct events writer was able to successfully directly write each event, that was read from the corresponding single-threaded buffer segment, to an event table at the data store; and

invoke the instance of an events file writer at that event capture thread, whenever the invoker determines that the corresponding instance of the direct events writer was unable to successfully write each event directly to the data store, to serialize the plurality of events from the particular single-threaded buffer segment to generate an events file and to write the events file to the TEFSS.

3. The system according to claim 1, wherein each events file comprises:

a file name;

a group identifier that uniquely identifies a group of events files that were generated during a particular time window; and

file information comprising a file type, and a plurality of events that are serialized.

4. The system according to claim 3, wherein the file name comprises:

an application server name of the application server that generated the events in the events file;

a creation date for each of the events in the events file; and

a thread identifier that specifies a name of a thread writing the events file.

5. The system according to claim 1, wherein the data store further comprises:

an events uploader job detail table that comprises a plurality of rows, wherein each row is configured to store an uploader job record that includes job detail information that points to a particular events file stored in the TEFSS, and further comprising;

wherein the events file uploader service further comprises;

an events uploader manager is configured to create an uploader job record that points to the particular events file stored at the TEFSS, and to write the uploader job record to the events uploader job detail table maintained at the data store.

6. The system according to claim 5, wherein each uploader job record comprises:

a cluster identifier that uniquely identifies a collection of instances that a grouped as a cluster;

an instance identifier that uniquely identifies a collection of application servers grouped as an instance;

an application server name of a particular application server;

a group identifier that uniquely identifies a group of events files that were generated during a particular time window;

a job started date that specifies when the particular events file was created; and

a job type that indicates either regular or backup.

7. The system according to claim 6, wherein each uploader job record further comprises:

a file name of the particular events file, and wherein each row of the events uploader job detail table includes a row key that is used by an events uploader manager to look up job detail information for a particular event file,

wherein the row key is defined by the combination of the instance identifier, the application server name, the group identifier, the file name, and the job started date.

8. The system according to claim 6, wherein the cluster identifier, the instance identifier, the application server name, and the job type are used to identify a particular instance of the events file uploader service that runs on a particular application server of the cluster.

9. The system according to claim 6, wherein each uploader job record further comprises:

a number of events that specifies the number of events for this particular events file;

a last updated time that indicates when the particular events file was last updated;

a number of retry attempts that specifies how many times the events file uploader service has attempted to process the particular events file; and

a status that indicates either running or completed.

10. The system according to claim 1, wherein the events file uploader service further comprises:

an events uploader manager that is configured to;

maintain each of the uploader job records that are stored in the events uploader job detail table; and

retrieve job detail information from particular uploader job records stored at the events uploader job detail table of the data store.

11. The system according to claim 10, wherein the events uploader manager is further configured to:

read, from the events uploader job detail table, the most recent uploader job record for the application server;

searching the most recent uploader job record for the application server for a starting group identifier that uniquely identifies a group of events files generated by the application server during a particular time window; and

determine from the most recent uploader job record whether a status for the most recent uploader job record indicates running or completed.

12. The system according to claim 11, wherein the events uploader manager is further configured to:

when the status of the most recent uploader job record indicates completed;

search the TFESS for an events file that includes the starting group identifier; and

determine whether an events file that is associated with the starting group identifier was able to be read from the TEFSS.

13. The system according to claim 12, when the events file that is associated with the starting group identifier was not able to be read from the TEFSS, wherein the events uploader manager is further configured to:

determine a next possible group identifier that uniquely identifies another group of events files generated by the application server during another particular time window;

determine whether the next possible group identifier is for a current time window;

when the next possible group identifier is not for the current time window, search the TFESS for an events file that includes the next possible group identifier without delay, or

when the next possible group identifier is for the current time window, wait for a time period before searching the TFESS for an events file that includes the next possible group identifier.

14. The system according to claim 12, when the events file that includes the starting group identifier was able to be read from the TEFSS, wherein the events uploader manager is further configured to:

instantiate a worker thread and assign the worker thread to the particular events file that was read, wherein the worker thread comprises;

a particular events file reader and a particular event loader; and

wherein the events uploader manager is configured to;

upsert the most recent uploader job record for the application server with updated job detail information at the events uploader job detail table of the data store;

wherein the events file reader is configured to;

read at least one events file for the application server from the TEFSS based on the job detail information retrieved from the events uploader job detail table, serialize the events from the events file and send the events to the event loader.

15. The system according to claim 14, wherein the events loader is configured to:

load and save each of the events from the events file to a row of an event table maintained at the data store;

wherein the events uploader manager is further configured to;

update, in the events uploader job detail table, the status of the uploader job record that corresponds to the events file to indicate completed;

delete the events file from the TEFSS; and

search the TFESS for another events file that includes the starting group identifier.

16. The system according to claim 11, when it is determined from the most recent uploader job record that status for the most recent uploader job record indicates running, wherein the events uploader manager is further configured to:

assign a worker thread for the particular events file that was read, wherein the worker thread comprises;

a particular events file reader and a particular event loader; and

wherein the events uploader manager is configured to;

upsert the most recent uploader job record for the application server with updated job detail information at the events uploader job detail table of the data store;

wherein the events file reader is configured to;

read the events file, serialize the events from the events file and send the events to the event loader.

17. The system according to claim 16, wherein the events loader is configured to:

load and save each of the events from the events file to a row of the event table maintained at the data store;

wherein the events uploader manager is further configured to;

update, in the events uploader job detail table, the status of the uploader job record that corresponds to the events file to indicate completed; and

delete the events file from the TEFSS, and

search the TFESS for another events file that includes the starting group identifier.

18. The system according to claim 11, when searching the most recent uploader job record for the application server for a starting group identifier, wherein the events uploader manager is further configured to:

determine whether the most recent uploader job record from the events uploader job detail table for the application server is null;

read the group identifier from the most recent uploader job record if the most recent uploader job record is not determined to be null; and

search the TFESS for an events file that includes the starting group identifier.

19. The system according to claim 18, wherein the events uploader manager is further configured to:

attempt to read a marker file for the application server from the TEFSS if the most recent uploader job record is determined to be null;

determine whether the marker file for the application server was read from the TEFSS;

read a group identifier stored in the marker file when the marker file for the application server was read from the TEFSS; and

search the TFESS for an events file that includes the group identifier stored in the marker file.

20. The system according to claim 19, wherein the events uploader manager is further configured to:

read a group identifier stored in a cache at the application server when the marker file for the application server was not read from the TEFSS;

create a marker file with the group identifier stored in the cache at the application server; and

search the TFESS for an events file that includes the group identifier stored in the marker file.

21. The system according to claim 1, wherein the data store is a non-relational, distributed database.

22. A non-transitory computer-readable medium including instructions, which when executed by a processor at an application server, are configurable to perform a method comprising:

receiving, at a capture service, events from a client application running on the application server, wherein the events are to be stored in a data store;

storing, via the capture service, the events in an in-memory buffer service comprising;

a bounded buffer that is implemented in physical memory at the application server, wherein the bounded buffer comprises a plurality of single-threaded buffer segments that are each configured to temporarily store some of the events until a flush operation is performed;

flushing the plurality of single-threaded buffer segments of the bounded buffer, wherein each particular single-threaded buffer segment includes the plurality of events;

instantiating, via a consumer executor service, a plurality of consumer threads that each corresponds to a particular single-threaded buffer segment, wherein each consumer thread comprises;

an instance of an events reader and an instance of a direct events writer;

reading, at the events reader of each consumer thread, the events flushed from the particular single-threaded buffer segment that corresponds to that consumer thread;

adding, at each direct events writer, an identifier to each the events;

at each direct events writer, attempting to directly write each event to the data store;

generating at least one events file that comprises the plurality of events received from the in-memory buffer service when those events are unable to be directly written to the data store;

writing each events file to a temporary events file storage system (TEFSS) that is configured to temporarily store each events file;

reading each events file from the TEFSS; and

writing the plurality of events from each events file that was read to the data store.

23. The non-transitory computer-readable medium of claim 22, wherein each of the event capture threads further comprises:

an instance of an invoker, wherein the method further comprises;

at each invoker, determining whether a corresponding instance of the direct events writer was able to successfully write the events, that were read from the particular single-threaded buffer segment, directly to an event table at the data store; and

whenever an instance of an invoker at one of the event capture thread determines that a corresponding instance of the direct events writer was unable to successfully write the events directly to the data store, invoking an instance of the events file writer at that event capture thread, and receiving the plurality of events from that corresponding instance of the direct events writer for that events file writer; and

serializing, at each instance of the events file writer, the plurality of events from the particular single-threaded buffer segment into an events file.

24. The non-transitory computer-readable medium of claim 22, wherein each events file comprises:

a file name;

a group identifier that uniquely identifies a group of events files that were generated during a particular time window; and

a plurality of events that are serialized.

25. The non-transitory computer-readable medium of claim 22, wherein an events file uploader service comprises:

an events uploader manager that is configured to maintain uploader job records stored in an events uploader job detail table of the data store, wherein each uploader job record comprises;

a group identifier that uniquely identifies a group of events files that were generated during a particular time window, and further comprising;

creating, via the events uploader manager, an uploader job record that comprises job detail information that points to a particular events file stored in the TEFSS; and

writing, via the events uploader manager, the uploader job record to the events uploader job detail table maintained at the data store.

26. The non-transitory computer-readable medium of claim 25, wherein the step of reading each events file from the TEFSS, comprises:

reading at the events uploader manager, from the events uploader job detail table, a most recent uploader job record for the application server;

searching, at the events uploader manager, the most recent uploader job record for the application server for a starting group identifier that uniquely identifies a group of events files generated by the application server during a particular time window;

determining, at the events uploader manager, from the most recent uploader job record whether a status for the most recent uploader job record indicates running or completed;

when the status of the most recent uploader job record indicates completed;

searching, at the events uploader manager, the TFESS for an events file that includes the starting group identifier; and

determining, at the events uploader manager, whether an events file that is associated with the starting group identifier was able to be read from the TEFSS;

when the events file that is associated with the starting group identifier was not able to be read from the TEFSS;

determining, at the events uploader manager, a next possible group identifier that uniquely identifies another group of events files generated by the application server during another particular time window; and

determining, at the events uploader manager, whether the next possible group identifier is for a current time window;

when the next possible group identifier is for the current time window, waiting for a time period; and

searching, at the events uploader manager, the TFESS for an events file that includes the next possible group identifier; and

when the next possible group identifier is not for the current time window, searching, at the events uploader manager, the TFESS for an events file that includes the next possible group identifier;

when the events file that includes the starting group identifier was able to be read from the TEFSS;

assigning, at the events uploader manager, a worker thread for the particular events file that was read, wherein the worker thread comprises;

a particular events file reader and a particular event loader;

upserting from the events uploader manager, at the events uploader job detail table of the data store, the most recent uploader job record for the application server with updated job detail information; and

at the events file reader;

reading at least one events file for the application server from the TEFSS based on the job detail information retrieved, serializing the events from the events file, and sending the events to the event loader;

wherein the step of writing the plurality of events from each events file that was read to the data store, comprises;

loading and saving, via the events loader, each of the events from each events file to a row of an event table maintained at the data store;

further comprising;

updating at the events uploader manager, in the events uploader job detail table, the status of the uploader job record that corresponds to the events file to indicate completed;

deleting, at the events uploader manager, the events file from the TEFSS; and

searching, at the events uploader manager, the TFESS for another events file that includes the starting group identifier.

27. The non-transitory computer-readable medium of claim 26, when it is determined from the most recent uploader job record that status for the most recent uploader job record indicates running, further comprising:

assigning, via the events uploader manager, a worker thread for the particular events file that was read, wherein the worker thread comprises;

a particular events file reader and a particular event loader;

upserting, at the events uploader job detail table of the data store via the events uploader manager, the most recent uploader job record for the application server with updated job detail information;

at the events file reader;

reading the events file that includes the starting group identifier, serializing the events from the events file and sending the events to the event loader;

wherein the step of writing the plurality of events from each events file that was read to the data store, comprises;

loading and saving, via the events loader, each of the events from each events file to a row of an event table maintained at the data store; and

further comprising;

updating, in the events uploader job detail table via the events uploader manager, the status of the uploader job record that corresponds to the events file to indicate completed;

deleting the events file from the TEFSS via the events uploader manager; and

searching, via the events uploader manager, the TFESS for another events file that includes the starting group identifier.

28. A computer-implemented method performed by an application server comprising an events file uploader service and an indirect events writer that is configured to instantiate a plurality of event capture threads each comprising an instance of an events file writer, the computer-implemented method comprising:

at a capture service;

receiving events generated by a client application running on the application server and to providing the events to an in-memory buffer service;

at an in-memory buffer service;

temporarily holding the events in a bounded buffer that is implemented in physical memory at the application server, wherein the bounded buffer comprises a plurality of single-threaded buffer segments that are each configured to temporarily hold some of the events received from the capture service until a flush operation is performed, wherein each particular single-threaded buffer segment holds a plurality of events;

at a consumer executor service;

instantiating a plurality of consumer threads that each correspond to a particular single-threaded buffer segment, wherein each consumer thread comprises;

an instance of an events reader that is configured to read events flushed from a corresponding single-threaded buffer segment and to add an identifier to each the events; and

an instance of a direct events writer that is configured to attempt to directly write each event to the data store;

invoking, when the events are unable to be directly written to the data store, an indirect events writer comprising;

a plurality of event capture threads;

at an events file writer of each event capture thread;

generating a particular events file that comprises the plurality of events received from the in-memory buffer service when those events are unable to be directly written to an event table at the data store;

writing the particular events file to a temporary events file storage system (TEFSS) that is configured to temporarily store one or more events files for subsequent writing to the data store;

invoking an events file uploader service that is configured to read at least one events file from the TEFSS, and then write the plurality of events from each of the retrieved events files

to the event table maintained at the data store.