diff options
Diffstat (limited to 'include/framework/structure')
| -rw-r--r-- | include/framework/structure/BufferView.h | 1 | ||||
| -rw-r--r-- | include/framework/structure/ExtensionStructure.h | 64 | ||||
| -rw-r--r-- | include/framework/structure/InternalLevel.h | 6 |
3 files changed, 42 insertions, 29 deletions
diff --git a/include/framework/structure/BufferView.h b/include/framework/structure/BufferView.h index 4e3de25..9e0872b 100644 --- a/include/framework/structure/BufferView.h +++ b/include/framework/structure/BufferView.h @@ -5,6 +5,7 @@ * * Distributed under the Modified BSD License. * + * TODO: This file is very poorly commented. */ #pragma once diff --git a/include/framework/structure/ExtensionStructure.h b/include/framework/structure/ExtensionStructure.h index 373a1e2..4802bc1 100644 --- a/include/framework/structure/ExtensionStructure.h +++ b/include/framework/structure/ExtensionStructure.h @@ -37,19 +37,23 @@ public: ~ExtensionStructure() = default; /* - * Create a shallow copy of this extension structure. The copy will share references to the - * same levels/shards as the original, but will have its own lists. As all of the shards are - * immutable (with the exception of deletes), the copy can be restructured with reconstructions - * and flushes without affecting the original. The copied structure will be returned with a reference - * count of 0; generally you will want to immediately call take_reference() on it. + * Create a shallow copy of this extension structure. The copy will share + * references to the same levels/shards as the original, but will have its + * own lists. As all of the shards are immutable (with the exception of + * deletes), the copy can be restructured with reconstructions and flushes + * without affecting the original. The copied structure will be returned + * with a reference count of 0; generally you will want to immediately call + * take_reference() on it. * - * NOTE: When using tagged deletes, a delete of a record in the original structure will affect - * the copy, so long as the copy retains a reference to the same shard as the original. This could - * cause synchronization problems under tagging with concurrency. Any deletes in this context will + * NOTE: When using tagged deletes, a delete of a record in the original + * structure will affect the copy, so long as the copy retains a reference + * to the same shard as the original. This could cause synchronization + * problems under tagging with concurrency. Any deletes in this context will * need to be forwarded to the appropriate structures manually. */ ExtensionStructure<R, S, Q, L> *copy() { - auto new_struct = new ExtensionStructure<R, S, Q, L>(m_buffer_size, m_scale_factor, m_max_delete_prop); + auto new_struct = new ExtensionStructure<R, S, Q, L>(m_buffer_size, m_scale_factor, + m_max_delete_prop); for (size_t i=0; i<m_levels.size(); i++) { new_struct->m_levels.push_back(m_levels[i]->clone()); } @@ -64,9 +68,9 @@ public: * setting the delete bit in its wrapped header. Returns 1 if a matching * record was found and deleted, and 0 if a matching record was not found. * - * This function will stop after finding the first matching record. It is assumed - * that no duplicate records exist. In the case of duplicates, this function will - * still "work", but in the sense of "delete first match". + * This function will stop after finding the first matching record. It is + * assumed that no duplicate records exist. In the case of duplicates, this + * function will still "work", but in the sense of "delete first match". */ int tagged_delete(const R &rec) { for (auto level : m_levels) { @@ -77,7 +81,7 @@ public: /* * If the record to be erased wasn't found, return 0. The - * DynamicExtension itself will then search the active + * DynamicExtension itself will then search the active * Buffers. */ return 0; @@ -164,21 +168,23 @@ public: } /* - * Validate that no level in the structure exceeds its maximum tombstone capacity. This is - * used to trigger preemptive compactions at the end of the reconstruction process. + * Validate that no level in the structure exceeds its maximum tombstone + * capacity. This is used to trigger preemptive compactions at the end of + * the reconstruction process. */ bool validate_tombstone_proportion() { - long double ts_prop; - for (size_t i=0; i<m_levels.size(); i++) { - if (m_levels[i]) { - ts_prop = (long double) m_levels[i]->get_tombstone_count() / (long double) calc_level_record_capacity(i); - if (ts_prop > (long double) m_max_delete_prop) { - return false; - } - } + long double ts_prop; + for (size_t i = 0; i < m_levels.size(); i++) { + if (m_levels[i]) { + ts_prop = (long double)m_levels[i]->get_tombstone_count() / + (long double)calc_level_record_capacity(i); + if (ts_prop > (long double)m_max_delete_prop) { + return false; + } } + } - return true; + return true; } bool validate_tombstone_proportion(level_index level) { @@ -224,14 +230,14 @@ public: /* * The amount of storage required for the reconstruction accounts * for the cost of storing the new records, along with the - * cost of retaining the old records during the process - * (hence the 2x multiplier). + * cost of retaining the old records during the process + * (hence the 2x multiplier). * - * FIXME: currently does not account for the *actual* size - * of the shards, only the storage for the records + * FIXME: currently does not account for the *actual* size + * of the shards, only the storage for the records * themselves. */ - size_t reccnt = m_levels[i-1]->get_record_count(); + size_t reccnt = m_levels[i - 1]->get_record_count(); if constexpr (L == LayoutPolicy::LEVELING) { if (can_reconstruct_with(i, reccnt)) { reccnt += m_levels[i]->get_record_count(); diff --git a/include/framework/structure/InternalLevel.h b/include/framework/structure/InternalLevel.h index d586869..db38946 100644 --- a/include/framework/structure/InternalLevel.h +++ b/include/framework/structure/InternalLevel.h @@ -6,6 +6,12 @@ * * Distributed under the Modified BSD License. * + * The word `Internal` in this class's name refers to memory. The current + * model, inherited from the framework in Practical Dynamic Extension for + * Sampling Indexes, would use a different ExternalLevel for shards stored + * on external storage. This is a distinction that can probably be avoided + * with some more thought being put into interface design. + * */ #pragma once |