Native ETag Support

[hamdaankhalid]

Native ETag Support

Garnet provides support for ETags on raw strings. You can associate any string-based key-value pair inserted into Garnet with an automatically updated ETag.
Compatibility with non-ETag commands and the behavior of data inserted with ETags are detailed in the markdown for garnet specific commands. Please read the markdown file for API contracts, and compatibility.

HLD:

RecordInfo for a record indicated whether or not a record contains an ETag. This bit on the record info is used to indicate that the first 8 bytes of the payload of the record include a long data type that represents the eTag associated with the value that is present after the first 8 bytes.

Reads don't modify the eTag, but any RMW operations do. Blind Upsert (SET) will remove the eTag unless sent with the RETAINETAG flag.

ETags are incremented on each update, and the user can use them to handle things such as caching and Optimistic concurrency control.

[TedHartMS]

Not finished with review yet but sending a few comments now

[hamdaankhalid]

BDN Benchmark

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My Branch:

BenchmarkDotNet v0.14.0, Windows 11 (10.0.26100.2605)
11th Gen Intel Core i7-1185G7 3.00GHz, 1 CPU, 8 logical and 4 physical cores
.NET SDK 8.0.404
[Host] : .NET 8.0.11 (8.0.1124.51707), X64 RyuJIT AVX-512F+CD+BW+DQ+VL+VBMI
.NET 8 : .NET 8.0.11 (8.0.1124.51707), X64 RyuJIT AVX-512F+CD+BW+DQ+VL+VBMI

Job=.NET 8 EnvironmentVariables=DOTNET_TieredPGO=0 Runtime=.NET 8.0
Server=True

Method	Params	Mean	Error	StdDev	Median	Allocated
Set	ACL	12.771 μs	0.2463 μs	0.3610 μs	12.818 μs	-
SetEx	ACL	17.118 μs	0.3363 μs	0.2981 μs	17.004 μs	-
SetNx	ACL	16.405 μs	0.3277 μs	0.4375 μs	16.344 μs	-
SetXx	ACL	17.048 μs	0.3363 μs	0.3737 μs	16.956 μs	-
GetFound	ACL	11.828 μs	0.2078 μs	0.3046 μs	11.723 μs	-
GetNotFound	ACL	7.912 μs	0.1527 μs	0.2090 μs	7.845 μs	-
Increment	ACL	21.251 μs	0.4103 μs	0.5189 μs	21.269 μs	-
Decrement	ACL	19.766 μs	0.2592 μs	0.2164 μs	19.833 μs	-
IncrementBy	ACL	24.148 μs	0.3647 μs	0.3412 μs	24.207 μs	-
DecrementBy	ACL	24.927 μs	0.4746 μs	0.5828 μs	24.911 μs	-
Set	AOF	17.906 μs	0.3573 μs	0.3168 μs	17.879 μs	-
SetEx	AOF	22.909 μs	0.4445 μs	0.6231 μs	22.849 μs	-
SetNx	AOF	22.423 μs	0.3564 μs	0.3333 μs	22.553 μs	-
SetXx	AOF	23.534 μs	0.3453 μs	0.3061 μs	23.467 μs	-
GetFound	AOF	12.305 μs	0.2387 μs	0.2344 μs	12.340 μs	-
GetNotFound	AOF	8.207 μs	0.1632 μs	0.2288 μs	8.165 μs	-
Increment	AOF	25.539 μs	0.5108 μs	0.9718 μs	25.361 μs	-
Decrement	AOF	26.609 μs	0.5270 μs	1.2214 μs	26.361 μs	-
IncrementBy	AOF	31.919 μs	0.6351 μs	1.2387 μs	31.642 μs	-
DecrementBy	AOF	31.978 μs	0.6143 μs	1.4479 μs	31.679 μs	-
Set	None	12.811 μs	0.2660 μs	0.7631 μs	12.502 μs	-
SetEx	None	17.352 μs	0.2739 μs	0.2428 μs	17.365 μs	-
SetNx	None	16.492 μs	0.2216 μs	0.1850 μs	16.500 μs	-
SetXx	None	17.265 μs	0.2120 μs	0.1983 μs	17.275 μs	-
GetFound	None	12.055 μs	0.2364 μs	0.2814 μs	12.169 μs	-
GetNotFound	None	8.140 μs	0.1539 μs	0.1773 μs	8.057 μs	-
Increment	None	21.646 μs	0.4279 μs	0.6405 μs	21.641 μs	-
Decrement	None	20.855 μs	0.3618 μs	0.3716 μs	21.011 μs	-
IncrementBy	None	24.285 μs	0.3506 μs	0.3279 μs	24.159 μs	-
DecrementBy	None	24.758 μs	0.3743 μs	0.3501 μs	24.879 μs	-

---

Commit: 635cd58 of main branch

BenchmarkDotNet v0.14.0, Windows 11 (10.0.22631.4602/23H2/2023Update/SunValley3)
11th Gen Intel Core i7-1185G7 3.00GHz, 1 CPU, 8 logical and 4 physical cores
.NET SDK 8.0.404
[Host] : .NET 8.0.11 (8.0.1124.51707), X64 RyuJIT AVX-512F+CD+BW+DQ+VL+VBMI
.NET 8 : .NET 8.0.11 (8.0.1124.51707), X64 RyuJIT AVX-512F+CD+BW+DQ+VL+VBMI

Job=.NET 8 EnvironmentVariables=DOTNET_TieredPGO=0 Runtime=.NET 8.0
Server=True

Method	Params	Mean	Error	StdDev	Allocated
Set	ACL	11.276 us	0.1586 us	0.1406 us	-
SetEx	ACL	15.780 us	0.1784 us	0.1582 us	-
SetNx	ACL	14.703 us	0.1184 us	0.0989 us	-
SetXx	ACL	15.647 us	0.1717 us	0.1522 us	-
GetFound	ACL	10.823 us	0.1988 us	0.1859 us	-
GetNotFound	ACL	7.523 us	0.1216 us	0.1078 us	-
Increment	ACL	18.174 us	0.2018 us	0.1888 us	-
Decrement	ACL	17.774 us	0.1349 us	0.1195 us	-
IncrementBy	ACL	23.203 us	0.2031 us	0.1900 us	-
DecrementBy	ACL	21.799 us	0.3914 us	0.3661 us	-
Set	AOF	15.909 us	0.2025 us	0.1894 us	-
SetEx	AOF	20.320 us	0.2052 us	0.1714 us	-
SetNx	AOF	20.636 us	0.3904 us	0.3260 us	-
SetXx	AOF	26.672 us	1.2831 us	3.6398 us	-
GetFound	AOF	15.404 us	0.2987 us	0.6234 us	-
GetNotFound	AOF	10.314 us	0.2044 us	0.3685 us	-
Increment	AOF	30.120 us	0.4504 us	0.7273 us	-
Decrement	AOF	29.597 us	0.5715 us	0.6803 us	-
IncrementBy	AOF	35.447 us	0.7080 us	0.7869 us	-
DecrementBy	AOF	36.219 us	0.6909 us	0.5394 us	-
Set	None	16.062 us	0.3177 us	0.6907 us	-
SetEx	None	21.791 us	0.4335 us	1.0132 us	-
SetNx	None	19.906 us	0.3903 us	0.8061 us	-
SetXx	None	20.788 us	0.3932 us	0.3678 us	-
GetFound	None	14.644 us	0.1330 us	0.1633 us	-
GetNotFound	None	10.337 us	0.2034 us	0.1699 us	-
Increment	None	25.026 us	0.4128 us	0.5786 us	-
Decrement	None	23.746 us	0.4415 us	0.4534 us	-
IncrementBy	None	29.509 us	0.5801 us	0.4529 us	-
DecrementBy	None	30.158 us	0.5956 us	0.7090 us	-