add a variant to ingest benchmark with shard-splitting disabled (#10876)

## Problem

we measure ingest performance for a few variants (stripe-sizes,
pre-sharded, shard-splitted).
However some phenomena (e.g. related to L0 compaction) in PS can be
better observed and optimized with un-sharded tenants.

## Summary of changes

- Allow to create projects with a policy that disables sharding
(`{"scheduling": "Essential"}`)
- add a variant to ingest_benchmark that uses that policy for the new
project

## Test run
https://github.com/neondatabase/neon/actions/runs/13396325970

.github/actions/neon-project-create/action.yml

@@ -19,7 +19,11 @@ inputs:
     default: '[1, 1]'
   # settings below only needed if you want the project to be sharded from the beginning
   shard_split_project:
-    description: 'by default new projects are not shard-split, specify true to shard-split'
+    description: 'by default new projects are not shard-split initiailly, but only when shard-split threshold is reached, specify true to explicitly shard-split initially'
+    required: false
+    default: 'false'
+  disable_sharding:
+    description: 'by default new projects use storage controller default policy to shard-split when shard-split threshold is reached, specify true to explicitly disable sharding'
     required: false
     default: 'false'
   admin_api_key:
@@ -107,6 +111,21 @@ runs:
             -H "Accept: application/json" -H "Content-Type: application/json" -H "Authorization: Bearer ${ADMIN_API_KEY}" \
             -d "{\"new_shard_count\": $SHARD_COUNT, \"new_stripe_size\": $STRIPE_SIZE}"
         fi
+        if [ "${DISABLE_SHARDING}" = "true" ]; then
+          # determine tenant ID
+          TENANT_ID=`${PSQL} ${dsn} -t -A -c "SHOW neon.tenant_id"`
+
+          echo "Explicitly disabling shard-splitting for project ${project_id} with tenant_id ${TENANT_ID}"
+
+          echo "Sending PUT request to https://${API_HOST}/regions/${REGION_ID}/api/v1/admin/storage/proxy/control/v1/tenant/${TENANT_ID}/policy"
+          echo "with body {\"scheduling\": \"Essential\"}"
+
+          # we need an ADMIN API KEY to invoke storage controller API for shard splitting (bash -u above checks that the variable is set)
+          curl -X PUT \
+            "https://${API_HOST}/regions/${REGION_ID}/api/v1/admin/storage/proxy/control/v1/tenant/${TENANT_ID}/policy" \
+            -H "Accept: application/json" -H "Content-Type: application/json" -H "Authorization: Bearer ${ADMIN_API_KEY}" \
+            -d "{\"scheduling\": \"Essential\"}"
+        fi
 
       env:
         API_HOST: ${{ inputs.api_host }}
@@ -116,6 +135,7 @@ runs:
         MIN_CU: ${{ fromJSON(inputs.compute_units)[0] }}
         MAX_CU: ${{ fromJSON(inputs.compute_units)[1] }}
         SHARD_SPLIT_PROJECT: ${{ inputs.shard_split_project }}
+        DISABLE_SHARDING: ${{ inputs.disable_sharding }}
         ADMIN_API_KEY: ${{ inputs.admin_api_key }}
         SHARD_COUNT: ${{ inputs.shard_count }}
         STRIPE_SIZE: ${{ inputs.stripe_size }}

.github/workflows/ingest_benchmark.yml

@@ -32,18 +32,27 @@ jobs:
           - target_project: new_empty_project_stripe_size_2048 
             stripe_size: 2048 # 16 MiB
             postgres_version: 16
+            disable_sharding: false
           - target_project: new_empty_project_stripe_size_32768
             stripe_size: 32768 # 256 MiB # note that this is different from null because using null will shard_split the project only if it reaches the threshold
                                # while here it is sharded from the beginning with a shard size of 256 MiB
+            disable_sharding: false
             postgres_version: 16
           - target_project: new_empty_project
             stripe_size: null # run with neon defaults which will shard split only when reaching the threshold
+            disable_sharding: false
             postgres_version: 16
           - target_project: new_empty_project
             stripe_size: null # run with neon defaults which will shard split only when reaching the threshold
+            disable_sharding: false
             postgres_version: 17
           - target_project: large_existing_project
             stripe_size: null # cannot re-shared or choose different stripe size for existing, already sharded project
+            disable_sharding: false
+            postgres_version: 16
+          - target_project: new_empty_project_unsharded
+            stripe_size: null # run with neon defaults which will shard split only when reaching the threshold
+            disable_sharding: true
             postgres_version: 16
       max-parallel: 1 # we want to run each stripe size sequentially to be able to compare the results
     permissions:
@@ -96,6 +105,7 @@ jobs:
         admin_api_key: ${{ secrets.NEON_STAGING_ADMIN_API_KEY }} 
         shard_count: 8
         stripe_size: ${{ matrix.stripe_size }}
+        disable_sharding: ${{ matrix.disable_sharding }} 
 
     - name: Initialize Neon project
       if: ${{ startsWith(matrix.target_project, 'new_empty_project') }}