The original patch was split in 3 new patches, addressing some concerns brough in the first version, about thread safety of data accessed without the lock held. It was also added an extra change to save the errno value before calling syslog. Original description of what the problem corrects follows: An user reports that their application connects to multiple servers through a rpc interface using libtirpc. When one of the servers misbehaves (goes down ungracefully or has a delay of a few seconds in the traffic flow), it was observed that the traffic from the client to other servers is decreased by the traffic anomaly of the failing server, i.e. traffic decreases or goes to 0 in all the servers. When investigated further, specifically into the behavior of the libtirpc at the time of the issue, it was observed that all of the application threads specifically interacting with libtirpc were locked into one single lock inside the libtirpc library. This was a race condition which had resulted in a deadlock and hence the resultant dip/stoppage of traffic. As an experiment, the user removed the libtirpc from the application build and used the standard glibc library for rpc communication. In that case, everything worked perfectly even in the time of the issue of server nodes misbehaving. Paulo Andrade (3): Make it clear rpc_createerr is thread safe Record errno value before calling syslog Do not hold a global mutex during connect src/clnt_vc.c | 24 ++++++++++++++---------- 1 file changed, 14 insertions(+), 10 deletions(-) -- 1.8.3.1 -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
