Event prioritization for an ordered event stream
Event prioritization for an ordered event stream (OES) is disclosed. Unlike conventional prioritization techniques, the disclosed subject matter can be performed by an OES data storage system to provide direct, rather than indirect, control of prioritization. In an embodiment, a prioritized hashed key (PHK) can be determined from an event characteristic and an indicated event priority value based on a selectable priority-sensitive hashing function. As such, events with a same key characteristic but different indicated priorities can have different PHKs, events with different key characteristics but the same indicated priority can have different PHKs, and events with the same key characteristic and the same priority can have a same PHK. An event priority can be inherently comprised in the PHK without needing to explicitly store the priority value with a written event in the OES. Moreover, the disclosed prioritization for the OES can be compatible with OES scaling techniques.
1. A system, comprising:
a processor; and
a memory that stores executable instructions that, when executed by the processor, facilitate performance of operations, comprising:
receiving a first event characteristic for a first event to be written to an ordered event stream being stored in an ordered event stream storage system;
determining a first prioritized hashed key value based on the first event characteristic and a first event priority value from event priority values; and
writing, to at least one storage device in the ordered event stream storage system, of the first event to the ordered event stream in accordance with the first prioritized hashed key value, wherein the first prioritized hashed key value directs the writing of the first event to an epoch associated with the ordered event stream that is correlated with an amount of delay associated with reading the first event based on the first event priority value.
2. The system of claim 1 , wherein the first event priority value is a default event priority value.
3. The system of claim 1 , wherein the first event priority value is a substitute for a default event priority value, and wherein the first event priority value corresponds to the first event to be written to the ordered event stream.
4. The system of claim 1 , wherein the determining of the first prioritized hashed key value results in a same prioritized hashed key value as a second prioritized hashed key value based on a second event characteristic that is the same as the first event characteristic and a second event priority value that is the same as the first event priority value, and wherein the second event characteristic and the second event priority value correspond to a second event to be written to the ordered event stream.
5. The system of claim 1 , wherein the determining of the first prioritized hashed key value results in a different prioritized hashed key value than a second prioritized hashed key value based on a second event characteristic and a second event priority value corresponding to a second event to be written to the ordered event stream.
6. The system of claim 5 , wherein the second event characteristic is a same event characteristic as the first event characteristic.
7. The system of claim 5 , wherein the second event priority value is a same event priority value as the first event priority value.
8. The system of claim 1 , wherein the first event is written according to the first prioritized hashed key value to a first epoch of the ordered event stream, and wherein a second event is to be written according to a second prioritized hashed key value to a second epoch of the ordered event stream.
9. The system of claim 8 , wherein a transition of the ordered event stream from the first epoch to the second epoch results in the first prioritized hashed key value being in a same prioritized hashed key range as the second prioritized hashed key value.
10. The system of claim 8 , wherein a transition of the ordered event stream from the first epoch to the second epoch results in the first prioritized hashed key value being in a different prioritized hashed key range than the second prioritized hashed key value.
11. The system of claim 10 , wherein the transition of the ordered event stream from the first epoch to the second epoch corresponds to an ordered event stream scaling operation.
12. The system of claim 10 , wherein the transition of the ordered event stream from the first epoch to the second epoch corresponds to a change in a count of event priority values represented by a hashed key space topology corresponding to the ordered event stream.
13. A method, comprising:
determining, by a system comprising a processor, a first prioritized hashed key value based on a first event characteristic and a first event priority value from event priority values, wherein the first event characteristic corresponds to a first event to be written to an ordered event stream being stored in an ordered event stream storage system; and
writing, by the system, to at least one storage device in the ordered event stream storage system, of the first event to the ordered event stream based on the first prioritized hashed key value, wherein the writing excludes explicitly storing the first event priority value in the first event, and wherein the first prioritized hashed key value directs the writing of the first event to an epoch associated with the ordered event stream that is correlated with an amount of delay associated with reading the first event based on the first event priority value.
14. The method of claim 13 , wherein the determining of the first prioritized hashed key value results in a different prioritized hashed key value than a second prioritized hashed key value based on a second event characteristic and a second event priority value corresponding to a second event to be written to the ordered event stream.
15. The method of claim 14 , wherein the second event characteristic is a same event characteristic as the first event characteristic.
16. The method of claim 14 , wherein the second event priority value is a same event priority value as the first event priority value.
17. A non-transitory machine-readable medium, comprising executable instructions that, when executed by a processor, facilitate performance of operations, comprising:
in response to receiving a first event characteristic corresponding to a first event to be written to an ordered event stream being stored in an ordered event stream storage system, determining a first prioritized hashed key value based on the first event characteristic and a first event priority value from event priority values, wherein the determining employs a hashing function that can be selected from among hashing functions; and
writing, to at least one storage device in the ordered event stream storage system, of the first event to the ordered event stream based on the first prioritized hashed key value, wherein the first prioritized hashed key value directs the writing of the first event to an epoch associated with the ordered event stream that is correlated with an amount of delay associated with reading the first event based on the first event priority value.
18. The non-transitory machine-readable medium of claim 17 , wherein the determining of the first prioritized hashed key value results in a different prioritized hashed key value than a second prioritized hashed key value based on a second event characteristic and a second event priority value corresponding to a second event to be written to the ordered event stream.
19. The non-transitory machine-readable medium of claim 18 , wherein the second event characteristic is a same event characteristic as the first event characteristic.
20. The non-transitory machine-readable medium of claim 18 , wherein the second event priority value is a same event priority value as the first event priority value.