Use configmap hack

It turns out that the problem discussed in the last commit is fixed by
kubernetes/minikube#13013. This is not present in a
minikube release yet, so we can't rely on it. That said, this commit introduces
a hack whereby the bootstrap is passed in a configmap. This limits the size of
the bootstrap with all the problems that come along with a low-entropy
experiment.

Signed-off-by: Brian L. Troutwine <[email protected]>

Author: blt

soaks/bin/run_experiment.sh

@@ -90,15 +90,6 @@ minikube mount "${SOAK_CAPTURE_DIR}:/captures" &
 CAPTURE_MOUNT_PID=$!
 popd
 
-pushd "${SOAK_ROOT}/tests/${SOAK_NAME}"
-mkdir --parents data
-# Mount the data directory. This is where the data that supports the test are
-# mounted into the minikube. The software running in the minikube will not write
-# to this directory.
-minikube mount "${SOAK_ROOT}/tests/${SOAK_NAME}/data:/data" &
-DATA_MOUNT_PID=$!
-popd
-
 pushd "${SOAK_ROOT}/tests/${SOAK_NAME}/terraform"
 terraform init
 terraform apply -var "type=${VARIANT}" -var "vector_image=${IMAGE}" -var "vector_cpus=${VECTOR_CPUS}" -var "lading_image=ghcr.io/blt/lading:sha-0da91906d56acc899b829cea971d79f13e712e21" -auto-approve -compact-warnings -input=false -no-color
@@ -108,7 +99,6 @@ sleep "${WARMUP_GRACE}"
 echo "[${VARIANT}] Recording captures to ${SOAK_CAPTURE_DIR}"
 sleep "${TOTAL_SAMPLES}"
 kill "${CAPTURE_MOUNT_PID}"
-kill "${DATA_MOUNT_PID}"
 popd
 
 pushd "${__dir}"

soaks/common/terraform/modules/lading_http_blackhole/variables.tf

@@ -15,5 +15,5 @@ variable "http-blackhole-yaml" {
 
 variable "lading_image" {
   description = "The lading image to run"
-  type = string
+  type        = string
 }

soaks/common/terraform/modules/lading_http_gen/main.tf

@@ -1,3 +1,14 @@
+resource "kubernetes_config_map" "lading_bootstrap" {
+  metadata {
+    name      = "lading-http-gen-bootstrap"
+    namespace = var.namespace
+  }
+
+  data = {
+    "bootstrap.log" = var.http-gen-static-bootstrap
+  }
+}
+
 resource "kubernetes_config_map" "lading" {
   metadata {
     name      = "lading-http-gen"
@@ -113,8 +124,8 @@ resource "kubernetes_deployment" "http-gen" {
         }
         volume {
           name = "data"
-          host_path {
-            path = "/data"
+          config_map {
+            name = kubernetes_config_map.lading_bootstrap.metadata[0].name
           }
         }
       }

soaks/common/terraform/modules/lading_http_gen/variables.tf

@@ -13,7 +13,14 @@ variable "http-gen-yaml" {
   type        = string
 }
 
+variable "http-gen-static-bootstrap" {
+  description = "Boostrap log to be used for static variant, mounted at /data/boostrap.log"
+  type        = string
+  default     = ""
+}
+
+
 variable "lading_image" {
   description = "The lading image to run"
-  type = string
+  type        = string
 }

soaks/common/terraform/modules/lading_splunk_hec_blackhole/variables.tf

@@ -15,5 +15,5 @@ variable "splunk-hec-blackhole-yaml" {
 
 variable "lading_image" {
   description = "The lading image to run"
-  type = string
+  type        = string
 }

soaks/common/terraform/modules/lading_splunk_hec_gen/variables.tf

@@ -15,5 +15,5 @@ variable "splunk-hec-gen-yaml" {
 
 variable "lading_image" {
   description = "The lading image to run"
-  type = string
+  type        = string
 }

soaks/common/terraform/modules/lading_tcp_gen/variables.tf

@@ -15,5 +15,5 @@ variable "tcp-gen-yaml" {
 
 variable "lading_image" {
   description = "The lading image to run"
-  type = string
+  type        = string
 }

soaks/tests/http_pipelines_blackhole/data/input.log renamed to soaks/tests/http_pipelines_blackhole/terraform/data/http_gen_bootstrap.log

@@ -4,12 +4,12 @@ prometheus_addr: "0.0.0.0:9090"
 targets:
   vector:
     headers: {}
-    target_uri: "http://vector:8282/v1/input"
+    target_uri: "http://vector:8282/"
     bytes_per_second: "500 Mb"
     parallel_connections: 10
     method:
       post:
         maximum_prebuild_cache_size_bytes: "256 Mb"
         variant:
           static:
-            static_path: "/tmp/input.log"
+            static_path: "/data/bootstrap.log"

soaks/tests/http_pipelines_blackhole/terraform/http_gen.yaml

@@ -44,10 +44,17 @@ module "vector" {
   depends_on   = [module.monitoring]
 }
 module "http-gen" {
-  source        = "../../../common/terraform/modules/lading_http_gen"
-  type          = var.type
-  http-gen-yaml = file("${path.module}/http_gen.yaml")
-  namespace     = kubernetes_namespace.soak.metadata[0].name
-  lading_image  = var.lading_image
-  depends_on    = [module.monitoring, module.vector]
+  source                    = "../../../common/terraform/modules/lading_http_gen"
+  type                      = var.type
+  http-gen-yaml             = file("${path.module}/http_gen.yaml")
+  # This is a hack. Ultimately this creates a configmap in the minikube, where
+  # we would _prefer_ to simply mount a directory into the kube. This is not
+  # possible, pending introductoin of
+  # https://github.com/kubernetes/minikube/issues/12301 into a release. Keep in
+  # mind that the bootstrap _must_ be below 1MB in size, which severely limits
+  # the entropy of our experiment.
+  http-gen-static-bootstrap = file("${path.module}/data/http_gen_bootstrap.log")
+  namespace                 = kubernetes_namespace.soak.metadata[0].name
+  lading_image              = var.lading_image
+  depends_on                = [module.monitoring, module.vector]
 }