X-Git-Url: http://git.vrable.net/?a=blobdiff_plain;f=bluesky%2Fcloudlog.c;h=4c671becf7b2eeac7f4e1c9f285c20494052b50d;hb=3380ff6d419c7d1370c95cf476520ed5398e5b6d;hp=6b802331da4dc8c6db9c47ace825e64cb5614f35;hpb=f2586554fd55cd3cc1be65ac33d1122d00372133;p=bluesky.git diff --git a/bluesky/cloudlog.c b/bluesky/cloudlog.c index 6b80233..4c671be 100644 --- a/bluesky/cloudlog.c +++ b/bluesky/cloudlog.c @@ -13,13 +13,9 @@ #include "bluesky-private.h" -/* The locations hash table in the file system is used to map objects to their locations. Objects are named using 128- */ - -typedef struct { - BlueSkyCloudID id; - - BlueSkyCloudPointer *cloud_loc; -} BlueSkyLocationEntry; +// Rough size limit for a log segment. This is not a firm limit and there are +// no absolute guarantees on the size of a log segment. +#define CLOUDLOG_SEGMENT_SIZE (4 << 20) BlueSkyCloudID bluesky_cloudlog_new_id() { @@ -91,7 +87,7 @@ BlueSkyCloudLog *bluesky_cloudlog_new(BlueSkyFS *fs) log->fs = fs; log->type = LOGTYPE_UNKNOWN; log->id = bluesky_cloudlog_new_id(); - log->pointers = g_array_new(FALSE, TRUE, sizeof(BlueSkyCloudID)); + log->links = g_array_new(FALSE, TRUE, sizeof(BlueSkyCloudLog *)); g_atomic_int_set(&log->refcount, 1); return log; @@ -135,7 +131,12 @@ void bluesky_cloudlog_unref(BlueSkyCloudLog *log) log->type = LOGTYPE_INVALID; g_mutex_free(log->lock); g_cond_free(log->cond); - g_array_unref(log->pointers); + for (int i = 0; i < log->links->len; i++) { + BlueSkyCloudLog *c = g_array_index(log->links, + BlueSkyCloudLog *, i); + bluesky_cloudlog_unref(c); + } + g_array_unref(log->links); bluesky_string_unref(log->data); g_free(log); } @@ -173,30 +174,36 @@ struct log_footer { struct logref refs[0]; }; +/* Ensure that a cloud log item is loaded in memory, and if not read it in. + * TODO: Make asynchronous, and make this also fetch from the cloud. Right now + * we only read from the log. Log item must be locked. */ +void bluesky_cloudlog_fetch(BlueSkyCloudLog *log) +{ + if (log->data != NULL) + return; + + g_assert((log->location_flags | log->pending_write) & CLOUDLOG_JOURNAL); + + log->data = bluesky_log_map_object(log->fs->log, log->log_seq, + log->log_offset, log->log_size); + + g_cond_broadcast(log->cond); +} + BlueSkyCloudPointer bluesky_cloudlog_serialize(BlueSkyCloudLog *log, - BlueSkyCloudLogState *state) + BlueSkyFS *fs) { + BlueSkyCloudLogState *state = fs->log_state; + if (log->location_flags & CLOUDLOG_CLOUD) { return log->location; } - g_print("Flushing object %s to cloud...\n", - bluesky_cloudlog_id_to_string(log->id)); - - for (int i = 0; i < log->pointers->len; i++) { - BlueSkyCloudID id = g_array_index(log->pointers, BlueSkyCloudID, i); - g_print(" ...checking reference %s...\n", - bluesky_cloudlog_id_to_string(id)); - g_mutex_lock(log->fs->lock); - BlueSkyCloudLog *log2 - = (BlueSkyCloudLog *)g_hash_table_lookup(log->fs->locations, &id); - // TODO: refcount - bluesky_cloudlog_fetch(log2); - g_assert(log2 != NULL); - bluesky_cloudlog_ref(log2); - g_mutex_unlock(log->fs->lock); - bluesky_cloudlog_serialize(log2, state); - bluesky_cloudlog_unref(log2); + for (int i = 0; i < log->links->len; i++) { + BlueSkyCloudLog *ref = g_array_index(log->links, + BlueSkyCloudLog *, i); + if (ref != NULL) + bluesky_cloudlog_serialize(ref, fs); } g_mutex_lock(log->lock); @@ -221,74 +228,34 @@ BlueSkyCloudPointer bluesky_cloudlog_serialize(BlueSkyCloudLog *log, log->location_flags |= CLOUDLOG_CLOUD; g_mutex_unlock(log->lock); - return log->location; -} - -static void find_inodes(gpointer key, gpointer value, gpointer user_data) -{ - BlueSkyCloudLogState *state = (BlueSkyCloudLogState *)user_data; - BlueSkyCloudLog *item = (BlueSkyCloudLog *)value; + if (state->data->len > CLOUDLOG_SEGMENT_SIZE) + bluesky_cloudlog_flush(fs); - if (item->type != LOGTYPE_INODE) - return; - - bluesky_cloudlog_ref(item); - state->inode_list = g_list_prepend(state->inode_list, item); + return log->location; } -void bluesky_cloudlog_write_log(BlueSkyFS *fs) +/* Finish up a partially-written cloud log segment and flush it to storage. */ +void bluesky_cloudlog_flush(BlueSkyFS *fs) { BlueSkyCloudLogState *state = fs->log_state; - if (state->data == NULL) - state->data = g_string_new(""); - - g_mutex_lock(fs->lock); - g_hash_table_foreach(fs->locations, find_inodes, state); - g_mutex_unlock(fs->lock); - - while (state->inode_list != NULL) { - BlueSkyCloudLog *log = (BlueSkyCloudLog *)state->inode_list->data; - bluesky_cloudlog_serialize(log, state); - bluesky_cloudlog_unref(log); - state->inode_list = g_list_delete_link(state->inode_list, - state->inode_list); - } - - if (state->data->len > 0) { - g_print("Serialized %zd bytes of data to cloud\n", state->data->len); - - BlueSkyStoreAsync *async = bluesky_store_async_new(fs->store); - async->op = STORE_OP_PUT; - async->key = g_strdup_printf("log-%08d-%08d", - state->location.directory, - state->location.sequence); - async->data = bluesky_string_new_from_gstring(state->data); - bluesky_store_async_submit(async); - bluesky_store_async_wait(async); - bluesky_store_async_unref(async); - - state->location.sequence++; - state->location.offset = 0; - } - - state->data = NULL; -} - -/* Ensure that a cloud log item is loaded in memory, and if not read it in. - * TODO: Make asynchronous, and make this also fetch from the cloud. Right now - * we only read from the log. Log item must be locked. */ -void bluesky_cloudlog_fetch(BlueSkyCloudLog *log) -{ - if (log->data != NULL) + if (state->data == NULL || state->data->len == 0) return; - g_print("Re-mapping log entry %d/%d/%d...\n", - log->log_seq, log->log_offset, log->log_size); + /* TODO: Append some type of commit record to the log segment? */ - g_assert(log->location_flags & CLOUDLOG_JOURNAL); + g_print("Serializing %zd bytes of data to cloud\n", state->data->len); - log->data = bluesky_log_map_object(log->fs->log, log->log_seq, - log->log_offset, log->log_size); + BlueSkyStoreAsync *async = bluesky_store_async_new(fs->store); + async->op = STORE_OP_PUT; + async->key = g_strdup_printf("log-%08d-%08d", + state->location.directory, + state->location.sequence); + async->data = bluesky_string_new_from_gstring(state->data); + bluesky_store_async_submit(async); + bluesky_store_async_wait(async); + bluesky_store_async_unref(async); - g_cond_broadcast(log->cond); + state->location.sequence++; + state->location.offset = 0; + state->data = g_string_new(""); }