private void ensureAcceleratorsIsMutable() {
          if (!((bitField0_ & 0x00000800) != 0)) {
            accelerators_ =
                new java.util.ArrayList<
                    com.google.cloud.workstations.v1beta.WorkstationConfig.Host.GceInstance
                        .Accelerator>(accelerators_);
            bitField0_ |= 0x00000800;
          }
        }
<pre>
Optional. The size of the boot disk for the VM in gigabytes (GB).
The minimum boot disk size is `30` GB. Defaults to `50` GB.
</pre>

<code>int32 boot_disk_size_gb = 9 [(.google.api.field_behavior) = OPTIONAL];</code>

@return This builder for chaining.
java-workstations/proto-google-cloud-workstations-v1beta/src/main/java/com/google/cloud/workstations/v1beta/WorkstationConfig.java