/*! \brief Detect low disk space situations on the generator and turn all logging off if not enough space is left.
When called, this function will check the amount of space left on the generator's "output" device / directory.
If the percentage of free space is lower than the treshold percentage, it will generate an error transaction "---DISK SPACE LOW IN LOG FOLDER FOR {y_hostname_generator}---" and turn all further logging off until the end of the test, using y_log_turn_off_permanently().
\note Scripts that call lr_debug_message() or the various y_lib() toggle functions to turn the loglevel back up may ignore this restriction.
Loadrunner does not protect the generators' disks from overflowing, even if the test is writing out a lot of information to the logs really quickly.
If a disk fills up on the generator or the disk the controller uses for results collation overflows there is no graceful recovery. Collation will fail and test results may be hard or impossible to recover.
This kind of situation can occur when temporary service disruptions happen (triggering a flood of 'log on error' messages), but also if runtime settings are incorrect and the test was configured to log *everything*.
In order to prevent this from happening scripts should regularly call to both y_disk_space_guard() and y_disk_space_usage_guard() with some reasonable limits.
\param [in] max_free_percentage The amount of free diskspace as a percentage of total space that will cause the logging to turn off.
\author Floris Kraak
*/
void y_disk_space_guard(double max_free_percentage)
{
char* hostname;
static int disk_space_warning_given = 0;
double free_space_percentage;
char* log_folder = lr_get_attrib_string("out");
// check already fired once before.
if( disk_space_warning_given )
{
// guard against accidental re-enablement of the logs by turning them off explicitly.
y_log_turn_off_permanently();
return;
}
free_space_percentage = y_get_free_disk_space_percentage(log_folder);
// data point
hostname = lr_get_host_name();
lr_save_string(hostname, "y_hostname_generator");
lr_user_data_point( lr_eval_string("disk_space_{y_hostname_generator}_free_percentage"), free_space_percentage);
if( free_space_percentage < max_free_percentage )
{
y_setup();
lr_set_transaction(lr_eval_string("---DISK SPACE LOW IN LOG FOLDER FOR {y_hostname_generator}---"), 0, LR_FAIL);
lr_error_message("Diskspace low on %s in folder %s. %.2lf%% remaining, exceeding the limit of %.21f%% Logging turned off for user id %d for the remainder of the test!",
hostname, log_folder, free_space_percentage, max_free_percentage, y_virtual_user_id);
disk_space_warning_given = 1; // turn off further warnings.
y_log_turn_off_permanently();
}
}
/*! \brief Detect excessive disk usage by the test and turn all further logging off if more than a specific limit number of mebibytes has been used.
When called, this function will check the amount of space used on the generator's "output" device / directory since the first call to this function.
If the amount of used space exceeds the treshold it will generate an error transaction "---DISK SPACE LOW IN LOG FOLDER FOR {y_hostname_generator}---" and turn all further logging off until the end of the test, using y_log_turn_off_permanently().
\note Scripts that call lr_debug_message() or the various y_lib() toggle functions to turn the loglevel back up may ignore this restriction.
Loadrunner does not protect the generators' disks from overflowing, even if the test is writing out a lot of information to the logs really quickly.
If a disk fills up on the generator or the disk the controller uses for results collation overflows there is no graceful recovery. Collation will fail and test results may be hard or impossible to recover.
This kind of situation can occur when temporary service disruptions happen (triggering a flood of 'log on error' messages), but also if runtime settings are incorrect and the test was configured to log *everything*.
\note Because of the way this measurement is done, it may also trigger if some other process on the same machine starts writing large amounts of data to the same device.
In order to prevent this from happening scripts should regularly call to both y_disk_space_guard() and y_disk_space_usage_guard() with some reasonable limits.
\note The contents of the generator's output folder will be transferred to the controller during collation. If the sum of the output directories for the generators exceed the size of that filesystem collation will fail, even if there is enough space on the generators. Therefore, set this low enough to make sure that if all generators output folders get filled to the limit the controller will still have enough space for it's collation process.
\param [in] limit_mebibytes_used The amount of mebibytes the test is allowed to used on the generator's target directory.
\author Floris Kraak
*/
void y_disk_space_usage_guard(double limit_mebibytes_used)
{
char* hostname;
char* log_folder = lr_get_attrib_string("out");
double free_mebibytes;
static double max_free_mebibytes = -1;
double mebibytes_used;
static int disk_space_warning_given = 0;
// check already fired once before.
if( disk_space_warning_given )
{
// guard against accidental re-enablement of the logs by turning them off explicitly.
y_log_turn_off_permanently();
return;
}
free_mebibytes = y_get_free_disk_space_in_mebibytes(log_folder);
lr_log_message("y_disk_space_usage_guard: current free: %f MB, max free: %f MB, limit: %f MB used in folder: %s",
free_mebibytes, max_free_mebibytes, limit_mebibytes_used, log_folder);
if(max_free_mebibytes < 0)
{
lr_log_message("Storing free space as detected maximum");
max_free_mebibytes = free_mebibytes;
return;
}
else if(max_free_mebibytes < free_mebibytes)
{
lr_output_message("Warning: Free disk space increased from %f to %f, test disk space usage measurements may have become unreliable.", max_free_mebibytes, free_mebibytes);
max_free_mebibytes = free_mebibytes;
return;
}
// Ok, so we used *something*. Now let's see if it exceeds our limit.
mebibytes_used = max_free_mebibytes - free_mebibytes;
// data points
hostname = lr_get_host_name();
lr_save_string(hostname, "y_hostname_generator");
lr_user_data_point( lr_eval_string("disk_space_{y_hostname_generator}_free_mebibytes"), free_mebibytes);
lr_user_data_point( lr_eval_string("disk_space_{y_hostname_generator}_used_mebibytes"), mebibytes_used);
if( mebibytes_used >= limit_mebibytes_used )
{
y_setup();
lr_set_transaction(lr_eval_string("---DISKSPACE USAGE TOO HIGH IN LOG FOLDER FOR {y_hostname_generator}---"), 0, LR_FAIL);
lr_output_message("Disk space used on host %s in folder %s was %f mebibytes, reaching the limit of %f. Logging turned off for user id %d for the remainder of the test!",
hostname, log_folder, mebibytes_used, limit_mebibytes_used, y_virtual_user_id);
disk_space_warning_given = 1; // turn off further warnings.
y_log_turn_off_permanently();
}
}
int y_rand()
{
if(!_y_random_seed_initialized)
{
if( _vUserID == NULL )
{
y_setup();
}
// Seed the random number generator for later use.
// To make it random enough for our purposes mix in the vuser id and the adress of the vuser group name.
// In case the script itself already initialized the random number generator, use a random number from
// there as well.
srand( time() + _vUserID + ((int)(_vUserGroup)) + rand() );
_y_random_seed_initialized = 1;
}
return rand();
}