You can click the pin icon
to pin a node so that it stays within the Node Editor view and retains its position and size even after a regraph.
indicates that the node is pinned and
indicates that it is unpinned.
You can select Options > Pin all nodes by default so that any new nodes you create are automatically pinned. You can also select the same option via the work area marking menus.
icon in the toolbar to pin or the
icon to unpin.
and
icons affects all of the nodes.