Some word triplets, such as "mugged names nail", are not valid
results from any 32 bit value. If used to decode a 32 bit value,
the result will therefore encode to a different word triplet.
Fix this by using random words converted from an actual random
bitstring, ensuring we always get valid triplets.
This ensures one can't instanciate a DNSResolver object by
mistake, but uses the singleton. A separate create static
function is added for cases where a new object is explicitely
needed.
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->output_txs+output_indices->txs->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->output_txs+output_indices->txs->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 > 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 (0f4a036437)
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).
Based on tewinget's update.
Make OpenAlias address format independent of existing DNS functions.
Add tests.
Test:
make debug-test
cd build/debug/tests/unit_tests
# test that regular DNS functions work, including IPv4 lookups.
# also test function that converts OpenAlias address format
make && ./unit_tests --gtest_filter=DNSResolver*
# test that OpenAlias addresses like donate@getmonero.org work from
# wallet tools
make && ./unit_tests --gtest_filter=AddressFromURL.Success
DNSSEC is now implemented with the hardcoded key from unbound.
This will need to be not hardcoded in the future, but is okay for now.
Unit tests updated for DNSSEC (as well as for the fact that, contrary to
previous assumption, example.com does not have a static IP address).
51e3579 Fixed bug in static linking boost on MINGW (Thomas Winget)
f78bb00 Hopefully fixes build on Windows for real this time (Thomas Winget)
2b0583b Hopefully fixes build on Windows (Thomas Winget)
9dab105 DNS checkpoint loading for testnet should now be correct (Thomas Winget)
52f9629 sending commands to forked daemon works on testnet now (Thomas Winget)
76289d0 Fix tests building -- function signatures changed (Thomas Winget)
db53e19 revert stop_daemon method to use correct exit (Thomas Winget)
96cbecf RPC calls for background daemon added in (Thomas Winget)
9193d6f Daemonize changes pulled in -- daemon builds (Thomas Winget)
Everything except actually *using* BlockchainBDB is wired up, but the db
itself is not yet working. Some error about user mem not large enough.
I think I know what this error means, but I can't determine the cause.
Notes: BerkeleyDB does not allow 0-indexing in its recno type databases,
so block numbers *in the database* will be 1-indexed. Modifications
to indexing have been made as needed.
+toc -doc -drmonero
Fixed the windows path, and improved logging and data
(for graph) logging, fixed some locks and added more checks.
Still there is a locking error,
not added by my patches, but present in master version
(locking of map/list of peers).
commands and options for network limiting
works very well e.g. for 50 KiB/sec up and down
ToS (QoS) flag
peer number limit
TODO some spikes in ingress/download
TODO problems when other up and down limit
added "otshell utils" - simple logging (with colors, text files channels)
Some BlockchainDB unit testing fleshed out (and working), rudimentary
linker flag for lmdb in CMakeLists, but should probably be done
"correctly" at some point (find it on whatever system you're building on
and all that jazz).
update for rebase (warptangent 2015-01-04)
fix conflicts with upstream CMakeLists.txt files
tests/CMakeLists.txt (remove edits from original commit)
b94b8cd Added unit test. Fails for Japanese for some reason. (Oran Juice)
4c8a628 Remove iostream header put in during testing (Oran Juice)
9875f5b Variable unique prefix lengths for seed (Oran Juice)
Note: DNSResolver does not yet *use* DNSSEC, but rather this commit is
preparation for including DNSSEC validation. The function in
src/wallet/wallet2.cpp that uses DNSResolver still needs its parameters
updated accordingly.