SQL Objects
This chapter introduces SQL objects additionally provided by PG-Strom.
Device Information
| Function | Result | Description |
|---|---|---|
gpu_device_name(int = 0) |
text |
It tells name of the specified GPU device. |
gpu_global_memsize(int = 0) |
bigint |
It tells amount of the specified GPU device in bytes. |
gpu_max_blocksize(int = 0) |
int |
It tells maximum block-size on the specified GPU device. 1024, in the currently supported GPU models. |
gpu_warp_size(int = 0) |
int |
It tells warp-size on the specified GPU device. 32, in the currently supported GPU models. |
gpu_max_shared_memory_perblock(int = 0) |
int |
It tells maximum shared memory size per block on the specified GPU device. |
gpu_num_registers_perblock(int = 0) |
int |
It tells total number of registers per block on the specified GPU device. |
gpu_num_multiptocessors(int = 0) |
int |
It tells number of SM(Streaming Multiprocessor) units on the specified GPU device. |
gpu_num_cuda_cores(int = 0) |
int |
It tells number of CUDA cores on the specified GPU device. |
gpu_cc_major(int = 0) |
int |
It tells major CC(Compute Capability) version of the specified GPU device. |
gpu_cc_minor(int = 0) |
int |
It tells minor CC(Compute Capability) version of the specified GPU device. |
gpu_pci_id(int = 0) |
int |
It tells PCI bus-id of the specified GPU device. |
Arrow_Fdw Supports
| Function | Result | Description |
|---|---|---|
pgstrom.arrow_fdw_truncate(regclass) |
bool |
It truncates contents of the specified Arrow_Fdw foreign table. Arrow_Fdw foreign table must be writable. |
GPU Data Frame Functions
| Function | Result | Description |
|---|---|---|
pgstrom.arrow_fdw_export_cupy(regclass, text[], int) |
text |
It exports the specified columns of Arrow_Fdw foreign table as cuPy's data frame(cupy.ndarray). GPU buffer shall be released automatically on session closed. |
pgstrom.arrow_fdw_export_cupy_pinned(regclass, text[], int) |
text |
It exports the specified columns of Arrow_Fdw foreign table as cuPy's data frame(cupy.ndarray), as pinned GPU buffer; that is available after the session closed. |
pgstrom.arrow_fdw_put_gpu_buffer(text) |
bool |
It unreference the GPU buffer that is exported with the above functions. |
pgstrom.arrow_fdw_unpin_gpu_buffer(text) |
bool |
It unpin the GPU buffer that is exported with the above functions. |
Test Data Generation
| Function | Result | Description |
|---|---|---|
pgstrom.random_setseed(int) |
void |
It initializes the random seed. |
pgstrom.random_int(float=0.0, bigint=0, bigint=INT_MAX) |
bigint |
It generates random data in bigint type within the range. |
pgstrom.random_float(float=0.0, float=0.0, float=1.0) |
float |
It generates random data in float type within the range. |
pgstrom.random_date(float=0.0, date='2015-01-01', date='2025-12-31') |
date |
It generates random data in date type within the range. |
pgstrom.random_time(float=0.0, time='00:00:00', time='23:59:59') |
time |
It generates random data in time type within the range. |
pgstrom.random_timetz(float=0.0, time='00:00:00', time='23:59:59') |
timetz |
It generates random data in timetz type within the range. |
pgstrom.random_timestamp(float=0.0, timestamp='2015-01-01', timestamp='2025-01-01') |
timestamp |
It generates random data in timestamp type within the range. |
pgstrom.random_macaddr(float=0.0, macaddr='ab:cd:00:00:00', macaddr='ab:cd:ff:ff:ff:ff') |
macaddr |
It generates random data in macaddr type within the range. |
pgstrom.random_inet(float=0.0, inet='192.168.0.1/16') |
inet |
It generates random data in inet type within the range. |
pgstrom.random_text(float=0.0, text='test_**') |
text |
It generates random data in text type. The '*' characters in 2nd argument shall be replaced randomly. |
pgstrom.random_text_len(float=0.0, int=10) |
text |
It generates random data in text type within the specified length. |
pgstrom.random_int4range(float=0.0, bigint=0, bigint=INT_MAX) |
int4range |
It generates random data in int4range type within the range. |
pgstrom.random_int8range(float=0.0, bigint=0, bigint=LONG_MAX) |
int8range |
It generates random data in int8range type within the range. |
pgstrom.random_tsrange(float=0.0, timestamp='2015-01-01', timestamp='2025-01-01') |
tsrange |
It generates random data in tsrange type within the range. |
pgstrom.random_tstzrange(float=0.0, timestamptz='2015-01-01', timestamptz='2025-01-01') |
tstzrange |
It generates random data in tstzrange type within the range. |
pgstrom.random_daterange(float=0.0, date='2015-01-01', date='2025-12-31') |
daterange |
It generates random data in daterange type within the range. |
Other Functions
| Function | Result | Description |
|---|---|---|
pgstrom.license_query() |
text |
It shows the active commercial subscription. |
System View
PG-Strom provides several system view to export its internal state for users or applications.
The future version may add extra fields here. So, it is not recommended to reference these information schemas using SELECT * FROM ....
pgstrom.device_info
pgstrom.device_into system view exports device attributes of the GPUs recognized by PG-Strom.
GPU has different specification for each model, like number of cores, capacity of global memory, maximum number of threads and etc, user's software should be optimized according to the information if you try raw GPU programming with PL/CUDA functions.
| Name | Data Type | Description |
|---|---|---|
| device_nr | int |
GPU device number |
| aindex | int |
Attribute index |
| attribute | text |
Attribute name |
| value | text |
Value of the attribute |
pgstrom.device_preserved_meminfo
pgstrom.device_preserved_meminfo system view exports information of the preserved device memory; which can be shared multiple PostgreSQL backend.
Right now, only Python collaboration of Arrow_Fdw uses this feature.
| Name | Data Type | Description |
|---|---|---|
| device_nr | int |
GPU device number |
| handle | bytea |
IPC handle of the preserved device memory |
| owner | regrole |
Owner of the preserved device memory |
| length | bigint |
Length of the preserved device memory in bytes |
| ctime | timestamp with time zone |
Timestamp when the preserved device memory is created |