Fast Ring Queue Save

1. What is a ring queue

• the data is "first in first out".
• prev data of queue head is the queue tail.
• the data of ring can reuse.

2. The advantages of ring queue

• Guaranteed elements are first-in, first-out

• Element space can be reused

• Provides an efficient mechanism for multithread data transfer.

3. Ring queue of work example

• Linux between kernel and system to transfor network data( PACKET_RX_RING and PACKET_TX_RING )

4. Actual test results

• In CentOS 5.5 (cpu per core frequency 1200MHz) .
• ring queue length is 10000, one element data size is 4 bytes
• [ring_test] the element writted and then to read is about 25 million per second.
• [notify_ring_test] the element writted and then to read is about 20 million per second.