code: func (pmc *proxyMetricsCollector) BlobPush(bytesPushed uint64) {
  	atomic.AddUint64(&pmc.blobMetrics.Requests, 1)
  	atomic.AddUint64(&pmc.blobMetrics.Hits, 1)
  	atomic.AddUint64(&pmc.blobMetrics.BytesPushed, bytesPushed)
  }
docs: // BlobPush tracks metrics about blobs pushed to clients