// zip64 extra header should be used.
			b.uint32(uint32max) // compressed size
			b.uint32(uint32max) // uncompressed size

			// append a zip64 extra block to Extra
			var buf [28]byte // 2x uint16 + 3x uint64
			eb := writeBuf(buf[:])
			eb.uint16(zip64ExtraID)
			eb.uint16(24) // size = 3x uint64
			eb.uint64(h.UncompressedSize64)
			eb.uint64(h.CompressedSize64)
			eb.uint64(h.offset)

	b.Write(buf[0:1])
	var cap0 int
	for i := 0; i < 5<<10; i++ {
		b.Write(buf)
		b.Read(buf)
		if i == 0 {
			cap0 = b.Cap()
		}
	}
	cap1 := b.Cap()
	// (*Buffer).grow allows for 2x capacity slop before sliding,
	// so set our error threshold at 3x.
	if cap1 > cap0*3 {
		t.Errorf("buffer cap = %d; too big (grew from %d)", cap1, cap0)
	}
}

func BenchmarkWriteByte(b *testing.B) {

- Improved FormatMap: Improves performance by about 4x, or nearly 2x in the worst case ([#112661](https://github.com/kubernetes/kubernetes/pull/112661), [@aimuz](https://github.com/aimuz)) [SIG Node]

### Migration

*   Add in-memory caching to the Dataset API.
*   Set default end_of_sequence variable in datasets iterators to false.
*   [Performance] Increase performance of `tf.layers.conv2d` when setting
    use_bias=True by 2x by using nn.bias_add.
*   Update iOS examples to use CocoaPods, and moved to tensorflow/examples/ios.
*   Adds a family= attribute in `tf.summary` ops to allow controlling the tab