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<title>monzero-core.git/src/cryptonote_core/CMakeLists.txt, branch v0.9.4</title>
<subtitle>Monzero core node, command-line wallet, consensus code, and release tooling.
</subtitle>
<id>https://code.monzero.org/monzero-core.git/atom?h=v0.9.4</id>
<link rel='self' href='https://code.monzero.org/monzero-core.git/atom?h=v0.9.4'/>
<link rel='alternate' type='text/html' href='https://code.monzero.org/monzero-core.git/'/>
<updated>2016-03-25T07:12:25Z</updated>
<entry>
<title>Merge pull request #749</title>
<updated>2016-03-25T07:12:25Z</updated>
<author>
<name>Riccardo Spagni</name>
<email>ric@spagni.net</email>
</author>
<published>2016-03-25T06:22:06Z</published>
<link rel='alternate' type='text/html' href='https://code.monzero.org/monzero-core.git/commit/?id=0d30b657859d6ebd3188bd16dfaa9c79c3dfcaa7'/>
<id>urn:sha1:0d30b657859d6ebd3188bd16dfaa9c79c3dfcaa7</id>
<content type='text'>
bfd4a28 Update BlockchainDB documentation (Thomas Winget)
797357e Change Doxyfile, Blockchain not blockchain_storage (Thomas Winget)
c835215 remove defunct code from cryptonote::core (Thomas Winget)
50dba6d cryptonote::core doxygen documentation (Thomas Winget)
8ac329d doxygen documentation for difficulty functions (Thomas Winget)
540a76c Move checkpoint functions into checkpoints class (Thomas Winget)
1b0c98e doxygen documentation for checkpoints.{h,cpp} (Thomas Winget)
89c24ac Remove unnecessary or defunct code (Thomas Winget)
ab0ed14 doxygen include private and static members (Thomas Winget)
3a48449 Updated documentation for blockchain.* (Thomas Winget)
</content>
</entry>
<entry>
<title>Revert "Merge pull request #749"</title>
<updated>2016-03-25T06:42:42Z</updated>
<author>
<name>Riccardo Spagni</name>
<email>ric@spagni.net</email>
</author>
<published>2016-03-25T06:42:42Z</published>
<link rel='alternate' type='text/html' href='https://code.monzero.org/monzero-core.git/commit/?id=01e0a69c175852adb01897431a138739faf39fe1'/>
<id>urn:sha1:01e0a69c175852adb01897431a138739faf39fe1</id>
<content type='text'>
This reverts commit 7fa63a82a1c3a0243f6757c1689855ed3ca61695, reversing
changes made to cb6be986c36b78eddb4b7f16e9ad440af8567dc4.
</content>
</entry>
<entry>
<title>Move checkpoint functions into checkpoints class</title>
<updated>2016-03-24T07:39:41Z</updated>
<author>
<name>Thomas Winget</name>
<email>tewinget@gmail.com</email>
</author>
<published>2015-10-08T02:28:37Z</published>
<link rel='alternate' type='text/html' href='https://code.monzero.org/monzero-core.git/commit/?id=540a76c5c29aa0742c00af4391ce718e7ec69c97'/>
<id>urn:sha1:540a76c5c29aa0742c00af4391ce718e7ec69c97</id>
<content type='text'>
The functions in src/cryptonote_core/checkpoints_create.{h,cpp} should
be member functions of the checkpoints class, if nothing else for the
sake of keeping their documentation together.

This commit covers moving those functions to be member functions of the
checkpoints class as well as documenting those functions.
</content>
</entry>
<entry>
<title>updated copyright year</title>
<updated>2015-12-31T06:39:56Z</updated>
<author>
<name>Riccardo Spagni</name>
<email>ric@spagni.net</email>
</author>
<published>2015-12-31T06:39:56Z</published>
<link rel='alternate' type='text/html' href='https://code.monzero.org/monzero-core.git/commit/?id=de0392685063d93dbdad3a6b1a2712eaf94dd51a'/>
<id>urn:sha1:de0392685063d93dbdad3a6b1a2712eaf94dd51a</id>
<content type='text'>
</content>
</entry>
<entry>
<title>Replace tabs with two spaces for consistency with rest of codebase</title>
<updated>2015-12-15T14:22:06Z</updated>
<author>
<name>warptangent</name>
<email>warptangent@tutanota.com</email>
</author>
<published>2015-12-14T04:54:39Z</published>
<link rel='alternate' type='text/html' href='https://code.monzero.org/monzero-core.git/commit/?id=725acc7f17e47e0ea0e7e690f241ee8a286411ea'/>
<id>urn:sha1:725acc7f17e47e0ea0e7e690f241ee8a286411ea</id>
<content type='text'>
Remove trailing whitespace in same files.
</content>
</entry>
<entry>
<title>New hardfork class</title>
<updated>2015-09-12T10:14:44Z</updated>
<author>
<name>moneromooo-monero</name>
<email>moneromooo-monero@users.noreply.github.com</email>
</author>
<published>2015-09-01T08:40:33Z</published>
<link rel='alternate' type='text/html' href='https://code.monzero.org/monzero-core.git/commit/?id=62b1f74116356653d17b4e2a71988de2d1ada093'/>
<id>urn:sha1:62b1f74116356653d17b4e2a71988de2d1ada093</id>
<content type='text'>
This keeps track of voting via block version, in order to decide
when to enable a particular fork's code.
</content>
</entry>
<entry>
<title>Fixed binary size issue due to embedded checkpoint data.</title>
<updated>2015-07-16T06:20:20Z</updated>
<author>
<name>NoodleDoodleNoodleDoodleNoodleDoodleNoo</name>
<email>xeven77@outlook.com</email>
</author>
<published>2015-07-12T04:24:42Z</published>
<link rel='alternate' type='text/html' href='https://code.monzero.org/monzero-core.git/commit/?id=2e293a563e3c237060638670d190dce467045868'/>
<id>urn:sha1:2e293a563e3c237060638670d190dce467045868</id>
<content type='text'>
Fixed OSX compilation issues due to random lmdb resize points.
Fixed infinite loop bug when calling core::get_block_template(..).
</content>
</entry>
<entry>
<title>** CHANGES ARE EXPERIMENTAL (FOR TESTING ONLY)</title>
<updated>2015-07-16T06:20:16Z</updated>
<author>
<name>NoodleDoodleNoodleDoodleNoodleDoodleNoo</name>
<email>xeven77@outlook.com</email>
</author>
<published>2015-07-10T20:09:32Z</published>
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<id>urn:sha1:e5d2680094ee15889934fe28901e4e133cda56f2</id>
<content type='text'>
Bockchain:
1. Optim: Multi-thread long-hash computation when encountering groups of blocks.
2. Optim: Cache verified txs and return result from cache instead of re-checking whenever possible.
3. Optim: Preload output-keys when encoutering groups of blocks. Sort by amount and global-index before bulk querying database and multi-thread when possible.
4. Optim: Disable double spend check on block verification, double spend is already detected when trying to add blocks.
5. Optim: Multi-thread signature computation whenever possible.
6. Patch: Disable locking (recursive mutex) on called functions from check_tx_inputs which causes slowdowns (only seems to happen on ubuntu/VMs??? Reason: TBD)
7. Optim: Removed looped full-tx hash computation when retrieving transactions from pool (???).
8. Optim: Cache difficulty/timestamps (735 blocks) for next-difficulty calculations so that only 2 db reads per new block is needed when a new block arrives (instead of 1470 reads).

Berkeley-DB:
1. Fix: 32-bit data errors causing wrong output global indices and failure to send blocks to peers (etc).
2. Fix: Unable to pop blocks on reorganize due to transaction errors.
3. Patch: Large number of transaction aborts when running multi-threaded bulk queries.
4. Patch: Insufficient locks error when running full sync.
5. Patch: Incorrect db stats when returning from an immediate exit from "pop block" operation.
6. Optim: Add bulk queries to get output global indices.
7. Optim: Modified output_keys table to store public_key+unlock_time+height for single transaction lookup (vs 3)
8. Optim: Used output_keys table retrieve public_keys instead of going through output_amounts-&gt;output_txs+output_indices-&gt;txs-&gt;output:public_key
9. Optim: Added thread-safe buffers used when multi-threading bulk queries.
10. Optim: Added support for nosync/write_nosync options for improved performance (*see --db-sync-mode option for details)
11. Mod: Added checkpoint thread and auto-remove-logs option.
12. *Now usable on 32-bit systems like RPI2.

LMDB:
1. Optim: Added custom comparison for 256-bit key tables (minor speed-up, TBD: get actual effect)
2. Optim: Modified output_keys table to store public_key+unlock_time+height for single transaction lookup (vs 3)
3. Optim: Used output_keys table retrieve public_keys instead of going through output_amounts-&gt;output_txs+output_indices-&gt;txs-&gt;output:public_key
4. Optim: Added support for sync/writemap options for improved performance (*see --db-sync-mode option for details)
5. Mod: Auto resize to +1GB instead of multiplier x1.5

ETC:
1. Minor optimizations for slow-hash for ARM (RPI2). Incomplete.
2. Fix: 32-bit saturation bug when computing next difficulty on large blocks.

[PENDING ISSUES]
1. Berkely db has a very slow "pop-block" operation. This is very noticeable on the RPI2 as it sometimes takes &gt; 10 MINUTES to pop a block during reorganization.
   This does not happen very often however, most reorgs seem to take a few seconds but it possibly depends on the number of outputs present. TBD.
2. Berkeley db, possible bug "unable to allocate memory". TBD.

[NEW OPTIONS] (*Currently all enabled for testing purposes)
1. --fast-block-sync arg=[0:1] (default: 1)
	a. 0 = Compute long hash per block (may take a while depending on CPU)
	b. 1 = Skip long-hash and verify blocks based on embedded known good block hashes (faster, minimal CPU dependence)
2. --db-sync-mode arg=[[safe|fast|fastest]:[sync|async]:[nblocks_per_sync]] (default: fastest:async:1000)
	a. safe = fdatasync/fsync (or equivalent) per stored block. Very slow, but safest option to protect against power-out/crash conditions.
	b. fast/fastest = Enables asynchronous fdatasync/fsync (or equivalent). Useful for battery operated devices or STABLE systems with UPS and/or systems with battery backed write cache/solid state cache.
	Fast    - Write meta-data but defer data flush.
	Fastest - Defer meta-data and data flush.
	Sync    - Flush data after nblocks_per_sync and wait.
	Async   - Flush data after nblocks_per_sync but do not wait for the operation to finish.
3. --prep-blocks-threads arg=[n] (default: 4 or system max threads, whichever is lower)
        Max number of threads to use when computing long-hash in groups.
4. --show-time-stats arg=[0:1] (default: 1)
	Show benchmark related time stats.
5. --db-auto-remove-logs arg=[0:1] (default: 1)
	For berkeley-db only. Auto remove logs if enabled.

**Note: lmdb and berkeley-db have changes to the tables and are not compatible with official git head version.
	At the moment, you need a full resync to use this optimized version.

[PERFORMANCE COMPARISON]
**Some figures are approximations only.
Using a baseline machine of an i7-2600K+SSD+(with full pow computation):
1. The optimized lmdb/blockhain core can process blocks up to 585K for ~1.25 hours + download time, so it usually takes 2.5 hours to sync the full chain.
2. The current head with memory can process blocks up to 585K for ~4.2 hours + download time, so it usually takes 5.5 hours to sync the full chain.
3. The current head with lmdb can process blocks up to 585K for ~32 hours + download time and usually takes 36 hours to sync the full chain.

Averate procesing times (with full pow computation):
lmdb-optimized:
1. tx_ave = 2.5 ms / tx
2. block_ave = 5.87 ms / block
memory-official-repo:
1. tx_ave = 8.85 ms / tx
2. block_ave = 19.68 ms / block
lmdb-official-repo (0f4a036437fd41a5498ee5e74e2422ea6177aa3e)
1. tx_ave = 47.8 ms / tx
2. block_ave = 64.2 ms / block

**Note: The following data denotes processing times only (does not include p2p download time)
lmdb-optimized processing times (with full pow computation):
1. Desktop,  Quad-core / 8-threads 2600k  (8Mb) - 1.25 hours processing time (--db-sync-mode=fastest:async:1000).
2. Laptop,   Dual-core / 4-threads U4200  (3Mb) - 4.90 hours processing time (--db-sync-mode=fastest:async:1000).
3. Embedded, Quad-core / 4-threads Z3735F (2x1Mb) - 12.0 hours processing time (--db-sync-mode=fastest:async:1000).

lmdb-optimized processing times (with per-block-checkpoint)
1. Desktop,  Quad-core / 8-threads 2600k  (8Mb) - 10 minutes processing time (--db-sync-mode=fastest:async:1000).

berkeley-db optimized processing times (with full pow computation)
1. Desktop, Quad-core / 8-threads 2600k  (8Mb) - 1.8 hours processing time (--db-sync-mode=fastest:async:1000).
2. RPI2. Improved from estimated 3 months(???) into 2.5 days (*Need 2AMP supply + Clock:1Ghz + [usb+ssd] to achieve this speed) (--db-sync-mode=fastest:async:1000).

berkeley-db optimized processing times (with per-block-checkpoint)
1. RPI2. 12-15 hours (*Need 2AMP supply + Clock:1Ghz + [usb+ssd] to achieve this speed) (--db-sync-mode=fastest:async:1000).
</content>
</entry>
<entry>
<title>Merge BlockchainDB into upstream</title>
<updated>2015-04-07T21:56:18Z</updated>
<author>
<name>Thomas Winget</name>
<email>tewinget@gmail.com</email>
</author>
<published>2015-04-07T21:56:18Z</published>
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<id>urn:sha1:a8bc7182eaa39d8be61f5e2ed9d98184e5820f17</id>
<content type='text'>
</content>
</entry>
<entry>
<title>Moved BlockchainDB into its own src/ subfolder</title>
<updated>2015-03-06T20:20:45Z</updated>
<author>
<name>Thomas Winget</name>
<email>tewinget@gmail.com</email>
</author>
<published>2015-03-06T20:20:45Z</published>
<link rel='alternate' type='text/html' href='https://code.monzero.org/monzero-core.git/commit/?id=5eab480cb116b7c58fe020951995815baa7ccd8f'/>
<id>urn:sha1:5eab480cb116b7c58fe020951995815baa7ccd8f</id>
<content type='text'>
Ostensibly janitorial work, but should be more relevant later down the
line.  Things that depend on core cryptonote things (i.e.
    cryptonote_core) don't necessarily depend on BlockchainDB and thus
have no need to have BlockchainDB baked in with them.
</content>
</entry>
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