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neon/pgxn/neon/file_cache.h
2025-05-29 15:54:55 +03:00

71 lines
2.2 KiB
C

/*-------------------------------------------------------------------------
*
* file_cache.h
* Local File Cache definitions
*
* Portions Copyright (c) 1996-2021, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
*-------------------------------------------------------------------------
*/
#ifndef FILE_CACHE_h
#define FILE_CACHE_h
#include "neon_pgversioncompat.h"
typedef struct FileCacheState
{
int32 vl_len_; /* varlena header (do not touch directly!) */
uint32 magic;
uint32 n_chunks;
uint32 n_pages;
uint16 chunk_size_log;
BufferTag chunks[FLEXIBLE_ARRAY_MEMBER];
/* followed by bitmap */
} FileCacheState;
/* GUCs */
extern bool lfc_store_prefetch_result;
extern int lfc_max_size;
extern int lfc_size_limit;
extern char *lfc_path;
/* functions for local file cache */
extern void lfc_invalidate(NRelFileInfo rinfo, ForkNumber forkNum, BlockNumber nblocks);
extern void lfc_writev(NRelFileInfo rinfo, ForkNumber forkNum,
BlockNumber blkno, const void *const *buffers,
BlockNumber nblocks);
/* returns number of blocks read, with one bit set in *read for each */
extern int lfc_readv_select(NRelFileInfo rinfo, ForkNumber forkNum,
BlockNumber blkno, void **buffers,
BlockNumber nblocks, bits8 *mask);
extern bool lfc_cache_contains(NRelFileInfo rinfo, ForkNumber forkNum,
BlockNumber blkno);
extern int lfc_cache_containsv(NRelFileInfo rinfo, ForkNumber forkNum,
BlockNumber blkno, int nblocks, bits8 *bitmap);
extern void lfc_init(void);
extern bool lfc_prefetch(NRelFileInfo rinfo, ForkNumber forknum, BlockNumber blkno,
const void* buffer, XLogRecPtr lsn);
extern FileCacheState* lfc_get_state(size_t max_entries);
extern void lfc_prewarm(FileCacheState* fcs, uint32 n_workers);
PGDLLEXPORT void lfc_prewarm_main(Datum main_arg);
static inline bool
lfc_read(NRelFileInfo rinfo, ForkNumber forkNum, BlockNumber blkno,
void *buffer)
{
bits8 rv = 0;
return lfc_readv_select(rinfo, forkNum, blkno, &buffer, 1, &rv) == 1;
}
static inline void
lfc_write(NRelFileInfo rinfo, ForkNumber forkNum, BlockNumber blkno,
const void *buffer)
{
return lfc_writev(rinfo, forkNum, blkno, &buffer, 1);
}
#endif /* FILE_CACHE_H */