diff --git a/ci3/aws_request_instance b/ci3/aws_request_instance
index 380a9de935c4..47f568b69a1e 100755
--- a/ci3/aws_request_instance
+++ b/ci3/aws_request_instance
@@ -2,12 +2,24 @@
 [ -n "${BUILD_SYSTEM_DEBUG:-}" ] && set -x # conditionally trace
 set -eu
 
-NAME=$1
-CPUS=$2
-ARCH=$3
+name=$1
+cpus=$2
+arch=$3
 
 cd $(dirname $0)
 
+bid_per_cpu_hour=0.03125
+
+instance_types_amd64=(
+  m6a
+  m7a
+  m7i
+)
+
+instance_types_arm64=(
+  m7g
+)
+
 # Declare an associative array to map CPU counts to instance type suffixes.
 declare -A cpu_map
 cpu_map=(
@@ -23,121 +35,26 @@ cpu_map=(
   [192]="48xlarge"
 )
 
-INSTANCE_TYPE_SUFFIX=${cpu_map[$CPUS]}
-
-# Check if INSTANCE_TYPE_SUFFIX is set, if not, the CPU count is not recognized.
-if [ -z "$INSTANCE_TYPE_SUFFIX" ]; then
-  >&2 echo "Unrecognized CPU count: $CPUS"
-  exit 1
-fi
-
-# Construct the full instance type. We use m6a/m7g currently.
-# Ami's are our custum built build-instance amis. See ami_update.sh.
-if [ "$ARCH" == "x86_64" ] || [ "$ARCH" == "amd64" ]; then
-  MACHINE_TYPE="m6a"
-  AMI=${AMI:-$(cat ./aws/ami_id_amd64)}
-elif [ "$ARCH" == "arm64" ]; then
-  MACHINE_TYPE="m7g"
-  AMI=${AMI:-$(cat ./aws/ami_id_arm64)}
+if [ "$arch" == "x86_64" ] || [ "$arch" == "amd64" ]; then
+  instances=("${instance_types_amd64[@]}")
+  ami=${ami:-$(cat ./aws/ami_id_amd64)}
+elif [ "$arch" == "arm64" ]; then
+  instances=("${instance_types_arm64[@]}")
+  ami=${ami:-$(cat ./aws/ami_id_arm64)}
 else
-  echo "Unknown arch: $ARCH"
+  echo "Unsupported arch: $arch" >&2
   exit 1
 fi
-INSTANCE_TYPE="$MACHINE_TYPE.$INSTANCE_TYPE_SUFFIX"
-
-export AWS_DEFAULT_REGION=us-east-2
-
-BID_PER_CPU_HOUR=0.03125
-PRICE=$(jq -n "$BID_PER_CPU_HOUR*$CPUS*100000 | round / 100000")
-
-launch_spec=$(cat <<EOF
-{
-  "ImageId": "$AMI",
-  "KeyName": "${KEY_NAME:-build-instance}",
-  "SecurityGroupIds": ["sg-0ccd4e5df0dcca0c9"],
-  "InstanceType": "$INSTANCE_TYPE",
-  "BlockDeviceMappings": [
-    {
-      "DeviceName": "/dev/sda1",
-      "Ebs": {
-        "VolumeSize": 64,
-        "VolumeType": "gp3",
-        "Throughput": 1000,
-        "Iops": 4000
-      }
-    }
-  ]
-}
-EOF
-)
 
-# Save the launch specification to a temporary file.
-temp_file=$(mktemp)
-trap "rm -f $temp_file" EXIT
-echo "$launch_spec" > "$temp_file"
-
-info="(name: $NAME) (ami: $AMI) (cpus: $CPUS) (bid: $PRICE)"
-
-if [ "${NO_SPOT:-0}" -ne 1 ]; then
-  >&2 echo "Requesting $INSTANCE_TYPE spot instance $info..."
-  SIR=$(aws ec2 request-spot-instances \
-    --spot-price "$PRICE" \
-    --instance-count 1 \
-    --type "one-time" \
-    --launch-specification file://$temp_file \
-    --query "SpotInstanceRequests[*].[SpotInstanceRequestId]" \
-    --output text)
-
-  >&2 echo "Waiting for instance id for spot request: $SIR..."
-  sleep 5
-  for I in {1..6}; do
-    IID=$(aws ec2 describe-spot-instance-requests \
-      --spot-instance-request-ids $SIR \
-      --query "SpotInstanceRequests[*].[InstanceId]" \
-      --output text)
-
-    [ -z "$IID" -o "$IID" == "None" ] || break
-
-    if [ $I -eq 6 ]; then
-      >&2 echo "Timeout waiting for spot request."
-      # Cancel spot request. We may still get allocated an instance if it's *just* happened.
-      aws ec2 cancel-spot-instance-requests --spot-instance-request-ids $SIR > /dev/null
+IFS=',' read -ra cpu_list <<< "$cpus"
+for cpu in "${cpu_list[@]}"; do
+  price=$(jq -n "$bid_per_cpu_hour*$cpu*100000 | round / 100000")
+  suffix=${cpu_map[$cpu]}
+  for inst in "${instances[@]}"; do
+    instance_type="$inst.$suffix"
+    if aws_request_instance_type $name $instance_type $price $ami; then
+      exit 0
     fi
-
-    sleep 5
   done
-fi
-
-if [ -z "${IID:-}" -o "${IID:-}" == "None" ]; then
-  # Request on-demand instance.
-  >&2 echo "Requesting $INSTANCE_TYPE on-demand instance $info..."
-  IID=$(aws ec2 run-instances \
-    --cli-input-json file://$temp_file \
-    --query "Instances[*].[InstanceId]" \
-    --output text)
-fi
-
-aws ec2 create-tags --resources $IID --tags "Key=Name,Value=$NAME"
-aws ec2 create-tags --resources $IID --tags "Key=Group,Value=build-instance"
-
-while [ -z "${IP:-}" ]; do
-  sleep 1
-  IP=$(aws ec2 describe-instances \
-    --filter "Name=instance-id,Values=$IID" \
-    --query "Reservations[*].Instances[*].PublicIpAddress" \
-    --output=text)
-done
-
-# Wait till ssh port is open.
->&2 echo "Waiting for SSH at $IP..."
-SECONDS=0
-SSH_CONFIG_PATH=${SSH_CONFIG_PATH:-aws/build_instance_ssh_config}
-[ "${NO_TERMINATE:-0}" -eq 1 ] && LIVE_CMD=true || LIVE_CMD="sudo shutdown -h +${AWS_SHUTDOWN_TIME:-60}"
-while ! ssh -F $SSH_CONFIG_PATH -o ConnectTimeout=1 $IP $LIVE_CMD > /dev/null 2>&1; do
-  if (( SECONDS >= 60 )); then
-    >&2 echo "Timeout: SSH could not login to $IP within 60 seconds."
-    exit 1
-  fi
-  sleep 1
 done
-echo $IP:${SIR:-}:$IID
+exit 1
diff --git a/ci3/aws_request_instance_type b/ci3/aws_request_instance_type
new file mode 100755
index 000000000000..6aae7df76657
--- /dev/null
+++ b/ci3/aws_request_instance_type
@@ -0,0 +1,104 @@
+#!/usr/bin/env bash
+[ -n "${BUILD_SYSTEM_DEBUG:-}" ] && set -x # conditionally trace
+set -eu
+
+NAME=$1
+INSTANCE_TYPE=$2
+PRICE=$3
+AMI=$4
+
+cd $(dirname $0)
+
+export AWS_DEFAULT_REGION=us-east-2
+
+launch_spec=$(cat <<EOF
+{
+  "ImageId": "$AMI",
+  "KeyName": "${KEY_NAME:-build-instance}",
+  "SecurityGroupIds": ["sg-0ccd4e5df0dcca0c9"],
+  "InstanceType": "$INSTANCE_TYPE",
+  "BlockDeviceMappings": [
+    {
+      "DeviceName": "/dev/sda1",
+      "Ebs": {
+        "VolumeSize": 64,
+        "VolumeType": "gp3",
+        "Throughput": 1000,
+        "Iops": 4000
+      }
+    }
+  ]
+}
+EOF
+)
+
+# Save the launch specification to a temporary file.
+temp_file=$(mktemp)
+trap "rm -f $temp_file" EXIT
+echo "$launch_spec" > "$temp_file"
+
+info="(name: $NAME) (type: $INSTANCE_TYPE) (ami: $AMI) (bid: $PRICE)"
+
+if [ "${NO_SPOT:-0}" -ne 1 ]; then
+  >&2 echo "Requesting $INSTANCE_TYPE spot instance $info..."
+  SIR=$(aws ec2 request-spot-instances \
+    --spot-price "$PRICE" \
+    --instance-count 1 \
+    --type "one-time" \
+    --launch-specification file://$temp_file \
+    --query "SpotInstanceRequests[*].[SpotInstanceRequestId]" \
+    --output text)
+
+  >&2 echo "Waiting for instance id for spot request: $SIR..."
+  sleep 5
+  for I in {1..6}; do
+    IID=$(aws ec2 describe-spot-instance-requests \
+      --spot-instance-request-ids $SIR \
+      --query "SpotInstanceRequests[*].[InstanceId]" \
+      --output text)
+
+    [ -z "$IID" -o "$IID" == "None" ] || break
+
+    if [ $I -eq 6 ]; then
+      >&2 echo "Timeout waiting for spot request."
+      # Cancel spot request. We may still get allocated an instance if it's *just* happened.
+      aws ec2 cancel-spot-instance-requests --spot-instance-request-ids $SIR > /dev/null
+    fi
+
+    sleep 5
+  done
+fi
+
+if [ -z "${IID:-}" -o "${IID:-}" == "None" ]; then
+  # Request on-demand instance.
+  >&2 echo "Requesting $INSTANCE_TYPE on-demand instance $info..."
+  IID=$(aws ec2 run-instances \
+    --cli-input-json file://$temp_file \
+    --query "Instances[*].[InstanceId]" \
+    --output text)
+fi
+
+aws ec2 create-tags --resources $IID --tags "Key=Name,Value=$NAME"
+aws ec2 create-tags --resources $IID --tags "Key=Group,Value=build-instance"
+
+while [ -z "${IP:-}" ]; do
+  sleep 1
+  IP=$(aws ec2 describe-instances \
+    --filter "Name=instance-id,Values=$IID" \
+    --query "Reservations[*].Instances[*].PublicIpAddress" \
+    --output=text)
+done
+
+# Wait till ssh port is open.
+>&2 echo "Waiting for SSH at $IP..."
+SECONDS=0
+SSH_CONFIG_PATH=${SSH_CONFIG_PATH:-aws/build_instance_ssh_config}
+[ "${NO_TERMINATE:-0}" -eq 1 ] && LIVE_CMD=true || LIVE_CMD="sudo shutdown -h +${AWS_SHUTDOWN_TIME:-60}"
+while ! ssh -F $SSH_CONFIG_PATH -o ConnectTimeout=1 $IP $LIVE_CMD > /dev/null 2>&1; do
+  if (( SECONDS >= 60 )); then
+    >&2 echo "Timeout: SSH could not login to $IP within 60 seconds."
+    exit 1
+  fi
+  sleep 1
+done
+echo $IP:${SIR:-}:$IID
diff --git a/ci3/bootstrap_ec2 b/ci3/bootstrap_ec2
index 3806e6c7d29b..14310375f969 100755
--- a/ci3/bootstrap_ec2
+++ b/ci3/bootstrap_ec2
@@ -12,9 +12,9 @@ if [ "$arch" == "arm64" ]; then
   export AWS_SHUTDOWN_TIME=90
 else
   if [ "$CI_FULL" -eq 1 ]; then
-    cores=192
+    cores=192,128,64
   else
-    cores=128
+    cores=128,64
   fi
 fi