Shared app queue takes more memory than port memory. To unmap all memory pages correct size need to be specified for munmap() call. Otherwise 4 Mb memory leaked on each configured application removal. The issue was introduced in 1d84b9e4b459.
For listen socket request reply port can be NULL if Router crashes immediately after issuing the request. Found by Coverity (CID 366310).
This patch is required to remove fragmented messages functionality.
This closes #467 issue on GitHub.
After WebSocket processing, the application port was released with incorrect
reason ("got request"), unnecessarily decrementing the active request counter.
The assertion was triggered only on application removal; a test was added
for this case.
The controller process awaits the response from the router for every configration change request. This patch adds error reporting for various error conditions which may happen because of file descriptors or memory shortage. Lack of a response lead to the controller awaiting the response, thus being unable to process other client reconfiguration requests that also became stuck.
Each application in router process required fd for a request queue shared memory. When the number of file descripts close to the limit, and port sockets successfully opened, router needs to properly handle the errors. This patch closes port sockets before destroying port structure to avoid file descriptors leakage and assertion in debug build.
This partially reverts the optimisation introduced in 1d84b9e4b459 to avoid an unpredictable block in nxt_unit_process_port_msg(). Under high load, this function may never return control to its caller, and the external event loop (in Node.js and Python asyncio) won't be able to process other scheduled events. To reproduce the issue, two request processing types are needed: 'fast' and 'furious'. The 'fast' one simply returns a small response, while the 'furious' schedules asynchronous calls to external resources. Thus, if Unit is subjected to a large amount of 'fast' requests, the 'furious' request processing freezes until the high load ends. The issue was found by Wu Jian Ping (@wujjpp) during Node.js stream implementation discussion and relates to PR #502 on GitHub.
ServerRequest now inherit stream Readable object. ServerResponse provides 'writable' property. Thanks to Wu Jian Ping (@wujjpp). This closes #274, closes #317 issues and closes #502 PR on GitHub.