diff options
-rw-r--r-- | release_docs/RELEASE.txt | 10 | ||||
-rw-r--r-- | src/H5FDros3.c | 73 |
2 files changed, 61 insertions, 22 deletions
diff --git a/release_docs/RELEASE.txt b/release_docs/RELEASE.txt index 0239a9e..19c7831 100644 --- a/release_docs/RELEASE.txt +++ b/release_docs/RELEASE.txt @@ -228,6 +228,16 @@ New Features Library: -------- + - Added a simple cache to the read-only S3 VFD + + The read-only S3 VFD now caches the first N bytes of a file stored + in S3 to avoid a lot of small I/O operations when opening files. + This cache is per-file and created when the file is opened. + + N is currently 4kiB or the size of the file, whichever is smaller. + + Addresses GitHub issue #3381 + - Added new API function H5Pget_actual_selection_io_mode() This function allows the user to determine if the library performed diff --git a/src/H5FDros3.c b/src/H5FDros3.c index 3f3413c..f704eff 100644 --- a/src/H5FDros3.c +++ b/src/H5FDros3.c @@ -43,6 +43,9 @@ */ #define ROS3_STATS 0 +/* Max size of the cache, in bytes */ +#define ROS3_MAX_CACHE_SIZE 4096 + /* The driver identification number, initialized at runtime */ static hid_t H5FD_ROS3_g = 0; @@ -189,6 +192,8 @@ typedef struct H5FD_ros3_t { H5FD_ros3_fapl_t fa; haddr_t eoa; s3r_t *s3r_handle; + uint8_t *cache; + size_t cache_size; #if ROS3_STATS ros3_statsbin meta[ROS3_STATS_BIN_COUNT + 1]; ros3_statsbin raw[ROS3_STATS_BIN_COUNT + 1]; @@ -1000,6 +1005,18 @@ H5FD__ros3_open(const char *url, unsigned flags, hid_t fapl_id, haddr_t maxaddr) HGOTO_ERROR(H5E_INTERNAL, H5E_UNINITIALIZED, NULL, "unable to reset file statistics"); #endif /* ROS3_STATS */ + /* Cache the initial bytes of the file */ + { + size_t filesize = H5FD_s3comms_s3r_get_filesize(file->s3r_handle); + + file->cache_size = (filesize < ROS3_MAX_CACHE_SIZE) ? filesize : ROS3_MAX_CACHE_SIZE; + + if (NULL == (file->cache = (uint8_t *)H5MM_calloc(file->cache_size))) + HGOTO_ERROR(H5E_VFL, H5E_NOSPACE, NULL, "unable to allocate cache memory"); + if (H5FD_s3comms_s3r_read(file->s3r_handle, 0, file->cache_size, file->cache) == FAIL) + HGOTO_ERROR(H5E_VFL, H5E_READERROR, NULL, "unable to execute read"); + } + ret_value = (H5FD_t *)file; done: @@ -1007,8 +1024,10 @@ done: if (handle != NULL) if (FAIL == H5FD_s3comms_s3r_close(handle)) HDONE_ERROR(H5E_VFL, H5E_CANTCLOSEFILE, NULL, "unable to close s3 file handle"); - if (file != NULL) + if (file != NULL) { + H5MM_xfree(file->cache); file = H5FL_FREE(H5FD_ros3_t, file); + } curl_global_cleanup(); /* early cleanup because open failed */ } /* end if null return value (error) */ @@ -1335,6 +1354,7 @@ H5FD__ros3_close(H5FD_t H5_ATTR_UNUSED *_file) #endif /* ROS3_STATS */ /* Release the file info */ + H5MM_xfree(file->cache); file = H5FL_FREE(H5FD_ros3_t, file); done: @@ -1666,41 +1686,50 @@ H5FD__ros3_read(H5FD_t *_file, H5FD_mem_t H5_ATTR_UNUSED type, hid_t H5_ATTR_UNU fprintf(stdout, "H5FD__ros3_read() called.\n"); #endif - assert(file != NULL); - assert(file->s3r_handle != NULL); - assert(buf != NULL); + assert(file); + assert(file->cache); + assert(file->s3r_handle); + assert(buf); filesize = H5FD_s3comms_s3r_get_filesize(file->s3r_handle); if ((addr > filesize) || ((addr + size) > filesize)) HGOTO_ERROR(H5E_ARGS, H5E_OVERFLOW, FAIL, "range exceeds file address"); - if (H5FD_s3comms_s3r_read(file->s3r_handle, addr, size, buf) == FAIL) - HGOTO_ERROR(H5E_VFL, H5E_READERROR, FAIL, "unable to execute read"); + /* Copy from the cache when accessing the first N bytes of the file. + * Saves network I/O operations when opening files. + */ + if (addr + size < file->cache_size) { + memcpy(buf, file->cache + addr, size); + } + else { + if (H5FD_s3comms_s3r_read(file->s3r_handle, addr, size, buf) == FAIL) + HGOTO_ERROR(H5E_VFL, H5E_READERROR, FAIL, "unable to execute read"); #if ROS3_STATS - /* Find which "bin" this read fits in. Can be "overflow" bin. */ - for (bin_i = 0; bin_i < ROS3_STATS_BIN_COUNT; bin_i++) - if ((unsigned long long)size < ros3_stats_boundaries[bin_i]) - break; - bin = (type == H5FD_MEM_DRAW) ? &file->raw[bin_i] : &file->meta[bin_i]; + /* Find which "bin" this read fits in. Can be "overflow" bin. */ + for (bin_i = 0; bin_i < ROS3_STATS_BIN_COUNT; bin_i++) + if ((unsigned long long)size < ros3_stats_boundaries[bin_i]) + break; + bin = (type == H5FD_MEM_DRAW) ? &file->raw[bin_i] : &file->meta[bin_i]; - /* Store collected stats in appropriate bin */ - if (bin->count == 0) { - bin->min = size; - bin->max = size; - } - else { - if (size < bin->min) + /* Store collected stats in appropriate bin */ + if (bin->count == 0) { bin->min = size; - if (size > bin->max) bin->max = size; - } - bin->count++; - bin->bytes += (unsigned long long)size; + } + else { + if (size < bin->min) + bin->min = size; + if (size > bin->max) + bin->max = size; + } + bin->count++; + bin->bytes += (unsigned long long)size; #endif /* ROS3_STATS */ + } done: FUNC_LEAVE_NOAPI(ret_value) |