diff options
| author | Eelco Dolstra <eelco.dolstra@logicblox.com> | 2012-12-11 11:49:42 +0100 |
|---|---|---|
| committer | Eelco Dolstra <eelco.dolstra@logicblox.com> | 2012-12-11 11:49:42 +0100 |
| commit | 772778c0eced8f8d63bfe6b1e9801ad6aada65bf (patch) | |
| tree | b93190ac1e556060923024d05cf79cfbf33a97f8 | |
| parent | e087bfef5f36f309b1c8d01bfe297e4cf4decb34 (diff) | |
On SQLITE_BUSY, wait a random amount of time
If all contending processes wait a fixed amount of time (100 ms),
there is a good probability that they'll just collide again.
| -rw-r--r-- | src/libmain/shared.cc | 6 | ||||
| -rw-r--r-- | src/libstore/local-store.cc | 2 |
2 files changed, 7 insertions, 1 deletions
diff --git a/src/libmain/shared.cc b/src/libmain/shared.cc index ead3fc017..e869ef037 100644 --- a/src/libmain/shared.cc +++ b/src/libmain/shared.cc @@ -10,6 +10,7 @@ #include <cctype> #include <exception> +#include <sys/time.h> #include <sys/stat.h> #include <unistd.h> @@ -135,6 +136,11 @@ static void initAndRun(int argc, char * * argv) everybody. */ umask(0022); + /* Initialise the PRNG. */ + struct timeval tv; + gettimeofday(&tv, 0); + srandom(tv.tv_usec); + /* Process the NIX_LOG_TYPE environment variable. */ string lt = getEnv("NIX_LOG_TYPE"); if (lt != "") setLogType(lt); diff --git a/src/libstore/local-store.cc b/src/libstore/local-store.cc index b4fc64d71..26b4cfd8c 100644 --- a/src/libstore/local-store.cc +++ b/src/libstore/local-store.cc @@ -48,7 +48,7 @@ static void throwSQLiteError(sqlite3 * db, const format & f) #if HAVE_NANOSLEEP struct timespec t; t.tv_sec = 0; - t.tv_nsec = 100 * 1000 * 1000; /* 0.1s */ + t.tv_nsec = (random() % 100) * 1000 * 1000; /* <= 0.1s */ nanosleep(&t, 0); #else sleep(1); |