Stress-Testing Software For Deep Space

kenekaplan writes "NASA has used VxWorks for several deep space missions, including Sojourner, Spirit, Opportunity and the Mars Reconnaissance Orbiter. When the space agency's Jet Propulsion Laboratory (JPL) needs to run stress tests or simulations for upgrades and fixes to the OS, Wind River's Mike Deliman gets the call. In a recent interview, Deliman, a senior member of the technical staff at Wind River, which is owned by Intel, gave a peek at the legacy technology under Curiosity's hood and recalled the emergency call he got when an earlier Mars mission hit a software snag after liftoff."

Re:I'm glad I don't program for NASA

[jimmydevice]

So, You work for Microsoft?

Re:Seems like a rationalization

[pedestrian crossing]

Pedestrian crossing?

You rang?

Re:"earlier Mars mission" == MER-A Spirit

[Anonymous Coward]

Malloc is non-deterministic. The request for a pointer to return contiguous free bytes will need to search a fragmented memory map to complete the request. The duration of the search depends upon the algorithms and the amount of fragmentation relative to the size of the request. It is worse if it must rearrange memory to accomodate the request. Thus, use of malloc() is typically avoided for time-critical code in a real-time operating system.