Link Shutdown Packet for Race Condition Prevention
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In high-speed data communications, a race condition can occur when a host sends a Link Shutdown Packet over a forward data link while the client is transmitting on a reverse data link, causing the reverse link to lose its transmission clock due to the forward link being in hibernation, leading to incomplete or lost data packets.
Innovation Solution
The system transmits a command to the client device over a first data link to revoke permission to transmit on the second data link, and initiates a delay before entering hibernation to ensure the client has completed its transmission, using N-phase polarity encoded data symbols and clocking to synchronize the second data link with the first, allowing orderly shutdown and hibernation of both links.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If the host sends a Link Shutdown Packet over the forward data link to shut down the link and enter hibernation, then power consumption is reduced and the link enters a low-power state, but the reverse data link may lose its transmission clock and cause data loss if the client is concurrently transmitting
Solution Approach 1:
The host sends a Link Shutdown Packet to the client before entering hibernation mode. This preliminary action allows the client to receive the shutdown command and complete any ongoing transmissions or flush buffers before the forward link enters hibernation, preventing data loss and clock synchronization issues on the reverse link
Solution Approach 2:
The Link Shutdown Packet acts as an intermediary signal between the host and client. It carries the shutdown instruction from the host to the client, allowing coordinated shutdown of both forward and reverse links without causing race conditions or data loss
2Productivity
If the host enters hibernation mode immediately after sending the shutdown command, then power management efficiency is improved, but the client may have incomplete transmission causing data packets to be lost
Solution Approach 1:
The system sends the Link Shutdown Packet as a preliminary action before entering hibernation. This gives the client advance notice to complete transmissions and flush buffers, ensuring no data is lost when the host enters hibernation mode
Solution Approach 2:
The client receives the Link Shutdown Packet and processes it to determine when to stop transmitting. This feedback mechanism ensures the client knows when to complete ongoing transmissions before the link shutdown takes effect, preventing data loss
Data Source
Figure 1
Figure 2
Figure 3
AI summary
System, methods and apparatus are described that facilitate data link shutdown between two devices within an electronic apparatus, enabling safe entry into a hibernation mode. A host device transmits a command to a client device over a first data link. If the client device is not transmitting over the second data link, the host devices initiates shut down of the first data link and entry to a hibernation state. A delay may be initiated when it is determined that the client device is transmitting on the second data link. The command may comprise an instruction revoking permission to transmit data over a second data link to cause the client device to terminate communication on the second data link.