NAME¶

pmemlog_ctl_get(), pmemlog_ctl_set(), pmemlog_ctl_exec() – Query and modify libpmemlog internal behavior (EXPERIMENTAL)

SYNOPSIS¶

#include <libpmemlog.h>
int pmemlog_ctl_get(PMEMlogpool *plp, const char *name, void *arg); (EXPERIMENTAL)
int pmemlog_ctl_set(PMEMlogpool *plp, const char *name, void *arg); (EXPERIMENTAL)
int pmemlog_ctl_exec(PMEMlogpool *plp, const char *name, void *arg); (EXPERIMENTAL)

DESCRIPTION¶

The pmemlog_ctl_get(), pmemlog_ctl_set() and pmemlog_ctl_exec() functions provide a uniform interface for querying and modifying the internal behavior of libpmemlog(7) through the control (CTL) namespace.

See more in pmem_ctl(5) man page.

CTL NAMESPACE¶

prefault.at_create | rw | global | int | int | - | boolean

If set, every page of the pool will be touched and written to when the pool is created, in order to trigger page allocation and minimize the performance impact of pagefaults. Affects only the pmemlog_create() function.

Always returns 0.

prefault.at_open | rw | global | int | int | - | boolean

If set, every page of the pool will be touched and written to when the pool is opened, in order to trigger page allocation and minimize the performance impact of pagefaults. Affects only the pmemlog_open() function.

Always returns 0.

sds.at_create | rw | global | int | int | - | boolean

If set, force-enables or force-disables SDS feature during pool creation. Affects only the pmemlog_create() function. See pmempool_feature_query(3) for informations about SDS (SHUTDOWN_STATE) feature.

Always returns 0.

CTL EXTERNAL CONFIGURATION¶

In addition to direct function call, each write entry point can also be set using two alternative methods.

The first method is to load a configuration directly from the PMEMLOG_CONF environment variable.

The second method of loading an external configuration is to set the PMEMLOG_CONF_FILE environment variable to point to a file that contains a sequence of ctl queries.

See more in pmem_ctl(5) man page.

SEE ALSO¶

libpmemlog(7), pmem_ctl(5) and <http://pmem.io>