assertion: fix thresholds to allow endpoints

This is actually what they implement. For example, some
testdata assertions we have (and which pass) today verify
that a metric does not change at all by providing an upper_bound
of zero for a `steady` assertion, which can only pass if the
metric is constant (equal to the mean).

Author: tbg

pkg/kv/kvserver/asim/assertion/assert.go

@@ -34,9 +34,9 @@ func (tht ThresholdType) String() string {
 	case ExactBound:
 		return "="
 	case UpperBound:
-		return "<"
+		return "≤"
 	case LowerBound:
-		return ">"
+		return "≥"
 	default:
 		panic("unknown threshold type")
 	}

pkg/kv/kvserver/asim/tests/testdata/non_rand/example_add_node.txt

@@ -19,7 +19,7 @@ add_node
 # Assert that the replica counts balance within 5% of each other among stores.
 assertion type=balance stat=replicas ticks=6 upper_bound=1.05
 ----
-asserting: max_{stores}(replicas)/mean_{stores}(replicas) < 1.05 at each of last 6 ticks
+asserting: max_{stores}(replicas)/mean_{stores}(replicas) ≤ 1.05 at each of last 6 ticks
 
 # Update the replication factor for the keyspace to be 3, instead of the
 # initial replication factor of 1 set during generation.
@@ -36,7 +36,7 @@ replicas#1: first: [s1=301, s2=0, s3=0] (stddev=141.89, mean=100.33, sum=301)
 replicas#1: last:  [s1=301, s2=271, s3=267] (stddev=15.17, mean=279.67, sum=839)
 artifacts[sma-count]: 866426beb5ad043b
 failed assertion sample 1
-  balance stat=replicas threshold=(<1.05) ticks=6
+  balance stat=replicas threshold=(≤1.05) ticks=6
 	max/mean=1.08 tick=0
 	max/mean=1.08 tick=1
 	max/mean=1.08 tick=2

pkg/kv/kvserver/asim/tests/testdata/non_rand/example_multi_store.txt

@@ -13,11 +13,11 @@ gen_load rate=7000 min_block=512 max_block=512
 
 assertion stat=leases type=balance ticks=6 upper_bound=1
 ----
-asserting: max_{stores}(leases)/mean_{stores}(leases) < 1.00 at each of last 6 ticks
+asserting: max_{stores}(leases)/mean_{stores}(leases) ≤ 1.00 at each of last 6 ticks
 
 assertion stat=leases type=steady ticks=6 upper_bound=0
 ----
-asserting: |leases(t)/mean_{T}(leases) - 1| < 0.00 ∀ t∈T and each store (T=last 6 ticks)
+asserting: |leases(t)/mean_{T}(leases) - 1| ≤ 0.00 ∀ t∈T and each store (T=last 6 ticks)
 
 eval duration=5m seed=42 metrics=(leases) cfgs=(sma-count,mma-only)
 ----
@@ -28,7 +28,7 @@ leases#1: first: [s1=8, s2=3, s3=0, s4=0, s5=0, s6=0, s7=0, s8=0, s9=1, s10=0, s
 leases#1: last:  [s1=4, s2=1, s3=0, s4=0, s5=0, s6=1, s7=0, s8=0, s9=1, s10=1, s11=1, s12=1, s13=2, s14=2] (stddev=1.07, mean=1.00, sum=14)
 artifacts[mma-only]: 3c31149bdddfe022
 failed assertion sample 1
-  balance stat=leases threshold=(<1.00) ticks=6
+  balance stat=leases threshold=(≤1.00) ticks=6
 	max/mean=4.00 tick=0
 	max/mean=4.00 tick=1
 	max/mean=4.00 tick=2

pkg/kv/kvserver/asim/tests/testdata/non_rand/example_rebalancing.txt

@@ -21,7 +21,7 @@ gen_load rate=7000 rw_ratio=0.95 access_skew=false min_block=128 max_block=256
 # seconds) the max/mean QPS of the cluster does not exceed 1.15.
 assertion stat=qps type=balance ticks=6 upper_bound=1.15
 ----
-asserting: max_{stores}(qps)/mean_{stores}(qps) < 1.15 at each of last 6 ticks
+asserting: max_{stores}(qps)/mean_{stores}(qps) ≤ 1.15 at each of last 6 ticks
 
 # The second is a steady state assertion. The steady state assertion requires
 # that during the last 6 ticks (60 seconds), the value of QPS per-store doesn't
@@ -32,7 +32,7 @@ asserting: max_{stores}(qps)/mean_{stores}(qps) < 1.15 at each of last 6 ticks
 # to take a duration, not ticks.
 assertion stat=qps type=steady ticks=6 upper_bound=0.05
 ----
-asserting: |qps(t)/mean_{T}(qps) - 1| < 0.05 ∀ t∈T and each store (T=last 6 ticks)
+asserting: |qps(t)/mean_{T}(qps) - 1| ≤ 0.05 ∀ t∈T and each store (T=last 6 ticks)
 
 # The generators are then called and 2 simulation runs, named samples are
 # created and evaluated. Each sample has a fixed duration of 3 minutes.
@@ -50,15 +50,15 @@ qps#1: last:  [s1=3999, s2=1997, s3=0, s4=0, s5=0, s6=1003, s7=0] (stddev=1413.6
 qps#2: last:  [s1=3996, s2=1996, s3=0, s4=0, s5=0, s6=1006, s7=0] (stddev=1412.60, mean=999.71, sum=6998)
 artifacts[mma-only]: c48e80aec15208d6
 failed assertion sample 1
-  balance stat=qps threshold=(<1.15) ticks=6
+  balance stat=qps threshold=(≤1.15) ticks=6
 	max/mean=4.00 tick=0
 	max/mean=4.00 tick=1
 	max/mean=4.00 tick=2
 	max/mean=4.00 tick=3
 	max/mean=4.00 tick=4
 	max/mean=4.00 tick=5
 failed assertion sample 2
-  balance stat=qps threshold=(<1.15) ticks=6
+  balance stat=qps threshold=(≤1.15) ticks=6
 	max/mean=4.00 tick=0
 	max/mean=4.00 tick=1
 	max/mean=4.00 tick=2
@@ -90,15 +90,15 @@ qps#1: last:  [s1=3995, s2=1998, s3=0, s4=0, s5=0, s6=1005, s7=0] (stddev=1412.5
 qps#2: last:  [s1=4000, s2=1995, s3=0, s4=0, s5=0, s6=1004, s7=0] (stddev=1413.71, mean=999.86, sum=6999)
 artifacts[mma-only]: fc6f065395b9a390
 failed assertion sample 1
-  balance stat=qps threshold=(<1.15) ticks=6
+  balance stat=qps threshold=(≤1.15) ticks=6
 	max/mean=4.00 tick=0
 	max/mean=4.00 tick=1
 	max/mean=4.00 tick=2
 	max/mean=4.00 tick=3
 	max/mean=4.00 tick=4
 	max/mean=4.00 tick=5
 failed assertion sample 2
-  balance stat=qps threshold=(<1.15) ticks=6
+  balance stat=qps threshold=(≤1.15) ticks=6
 	max/mean=4.00 tick=0
 	max/mean=4.00 tick=1
 	max/mean=4.00 tick=2

pkg/kv/kvserver/asim/tests/testdata/non_rand/example_splitting.txt

@@ -22,7 +22,7 @@ setting split_qps_threshold=2500
 # ticks of the simulation.
 assertion stat=replicas type=steady ticks=6 upper_bound=0.00
 ----
-asserting: |replicas(t)/mean_{T}(replicas) - 1| < 0.00 ∀ t∈T and each store (T=last 6 ticks)
+asserting: |replicas(t)/mean_{T}(replicas) - 1| ≤ 0.00 ∀ t∈T and each store (T=last 6 ticks)
 
 
 # Examine the number of replicas. Here there were 5 load based splits. This