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NdbAddingErrorInjection

A list of injectable errors is kept in storage/ndb/src/kernel/blocks/ERROR_codes.txt

Look at the latest numbers in the latest trees so that you get a new one. Each block starts at a particular offset.

A patch adding an error code may look like:

--- 1.27/storage/ndb/src/kernel/blocks/ERROR_codes.txt  2006-10-18 18:19:21 +10:00
+++ 1.28/storage/ndb/src/kernel/blocks/ERROR_codes.txt  2006-10-18 18:19:21 +10:00
@@ -8,7 +8,7 @@
 Next DBDIH 7178
 Next DBTC 8038
 Next CMVMI 9000
-Next BACKUP 10022
+Next BACKUP 10036
 Next DBUTIL 11002
 Next DBTUX 12008
 Next SUMA 13001

You also (should) add a description in the appropriate section. In this patch hunk, this documents (somewhat poorly) errors 10031 through 10035.

@@ -411,6 +411,11 @@
 10028: Abort backup by error at reception of BACKUP_FRAGMENT_CONF at master (code 305)
 10029: Abort backup by error at reception of FSAPPENDCONF in slave (FileOrScanError = 5)
 10030: Simulate buffer full from trigger execution => abort backup
+10031: Error 331 for dictCommitTableMutex_locked
+10032: backup checkscan
+10033: backup checkscan
+10034: define backup reply error
+10035: Fail to allocate buffers

 11001: Send UTIL_SEQUENCE_REF (in master)

In your code, you can check the result of ERROR_INSERTED(number) and perform an action if that error is inserted. An example of an error injection of failing to seize some pages is:

if(ERROR_INSERTED(10035) || files[i].p->pages.seize(noOfPages[i]) == false)
{
   jam();
   DEBUG_OUT("Failed to seize " << noOfPages[i] << " pages");
   defineBackupRef(signal, ptr, DefineBackupRef::FailedToAllocateBuffers);
}

The aim of this is to "fail" to seize the pages needed and test the failure code (signaled by sending the REFused signal).

You can also insert a crash if a particular error has been inserted. e.g.

CRASH_INSERTION((10001));