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| #include "postgres.h" | ||
| #include <time.h> |
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| else if (strncmp(action, "error-prob-", 11) == 0) | ||
| { | ||
| condition.prob = action2prob(action, 11); | ||
| function = "injection_error_prob"; | ||
| } |
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why error-prob-n-nnnnn and not a suffix that's accepted by strtod? It would simplify action2prob significantly, as it wouldn't need the local copy.
Additionally, couldn't we just pass a pointer to the expected numeric suffix of the action (action + 11, or &action[11])?
| return; | ||
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| /* Use the probability stored in the condition. */ | ||
| if ((double) rand() / (double) RAND_MAX > condition->prob) |
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Why not store condition->prob as fraction of RAND_MAX?
That way, we wouldn't have to do expensive double division and compare operations every time this injection point is hit.
So, condition->prob would equal probability * RAND_MAX, which cancels out with the / (double) RAND_MAX used here, and allows us to directly compare rand() > condition->prob
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We need to test SMGR failures.
This PR adds probability-based injection in the injection_points extension – New error-prob- action so injection points can raise an ERROR with a configurable probability (e.g. for fault-injection tests).