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

Commit: 4e327b4 of my 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	Median	Allocated
Set	ACL	13.102 μs	0.4563 μs	1.3165 μs	12.776 μs	-
SetEx	ACL	17.341 μs	0.5056 μs	1.4094 μs	16.800 μs	-
SetNx	ACL	15.394 μs	0.3004 μs	0.3689 μs	15.381 μs	-
SetXx	ACL	16.160 μs	0.2877 μs	0.2402 μs	16.139 μs	-
GetFound	ACL	12.472 μs	0.5838 μs	1.6371 μs	12.037 μs	-
GetNotFound	ACL	7.989 μs	0.1579 μs	0.2966 μs	7.954 μs	-
Increment	ACL	18.597 μs	0.3277 μs	0.3065 μs	18.587 μs	-
Decrement	ACL	18.344 μs	0.3614 μs	0.3867 μs	18.358 μs	-
IncrementBy	ACL	23.720 μs	0.4204 μs	0.3933 μs	23.652 μs	-
DecrementBy	ACL	23.773 μs	0.4573 μs	1.0779 μs	23.483 μs	-
Set	AOF	16.430 μs	0.3162 μs	0.6015 μs	16.355 μs	-
SetEx	AOF	21.385 μs	0.2904 μs	0.2575 μs	21.334 μs	-
SetNx	AOF	20.749 μs	0.3717 μs	0.3295 μs	20.597 μs	-
SetXx	AOF	21.634 μs	0.3568 μs	0.3163 μs	21.618 μs	-
GetFound	AOF	11.011 μs	0.1476 μs	0.1757 μs	11.000 μs	-
GetNotFound	AOF	7.725 μs	0.1019 μs	0.0903 μs	7.735 μs	-
Increment	AOF	23.524 μs	0.4212 μs	0.3734 μs	23.641 μs	-
Decrement	AOF	23.032 μs	0.3912 μs	0.3267 μs	23.039 μs	-
IncrementBy	AOF	28.487 μs	0.3811 μs	0.3379 μs	28.507 μs	-
DecrementBy	AOF	29.484 μs	0.4923 μs	0.8225 μs	29.358 μs	-
Set	None	11.608 μs	0.2198 μs	0.1948 μs	11.586 μs	-
SetEx	None	16.549 μs	0.3266 μs	0.3495 μs	16.528 μs	-
SetNx	None	15.839 μs	0.2813 μs	0.3851 μs	15.867 μs	-
SetXx	None	16.661 μs	0.3124 μs	0.2922 μs	16.608 μs	-
GetFound	None	11.618 μs	0.2289 μs	0.4976 μs	11.512 μs	-
GetNotFound	None	8.731 μs	0.1669 μs	0.1786 μs	8.720 μs	-
Increment	None	19.210 μs	0.2462 μs	0.2303 μs	19.221 μs	-
Decrement	None	19.306 μs	0.2564 μs	0.2398 μs	19.368 μs	-
IncrementBy	None	22.566 μs	0.3320 μs	0.2772 μs	22.464 μs	-
DecrementBy	None	23.824 μs	0.4657 μs	0.4129 μs	23.924 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	-