More docs, example, and fixing the free page diagnostic function for mutable transactions

[?]

Feb 21, 2021, 11:16 PM

5LSYTRQ6IOVUW26VJW5SWGFEIB7T2N4PVEB6VMNMR5ZHQ75MFOQAC

Dependencies

[2] FZBLNBGN Diagnostic tools (add_refs, check_free) + cleanup
[3] 6DCQHIFP Minor changes after benchmarking
[4] PXF3R6SV Improving test coverage for btree::cursor
[5] G4JEQLLX Debugging synchronisation
[6] OFINGD26 implementing prev() on cursors (+ some cleanup)
[7] YWFYZNLZ Cleanup + inter-process concurrency
[8] 6UVFCERM Formatting, debugging, etc.
[9] OTWDDJE7 Trait/type cleanup
[10] E4MD6T3L Proofreading and commenting of this crate (massive bug fixes included)
[11] OHUZ73MK Versions
[12] AFKBHYVE Comparing the two implementations of leaves (sized/unsized). Sized are faster for writes, slower for reads.
[13] AOX2XQIS Actually, with the correct functions, Unsized pages are always slower than Sized pages (especially for writing)
[14] T7QB6QEP Adding debug.rs
[15] OP6SVMOD Resetting history
[*] UAQX27N4 Tests
[*] W2MIZD5B Single file databases + CRC for the root pages (checking the other pages makes everything very slow)

Change contents

replacement in sanakirja/src/tests.rs at line 481

[3.11860]→[3.116:143](∅→∅)

let n = 10_000_000u64;

[3.11860]

[3.11974]

let n = 1_000u64;
edit in sanakirja/src/tests.rs at line 504

[3.2624]

[2.1098]

add_free_refs_mut(&mut txn, &mut refs).unwrap();
replacement in sanakirja/src/tests.rs at line 510

[3.413]→[3.12602:12694](∅→∅),[3.12602]→[3.12602:12694](∅→∅)

let mut db = create_db_::<MutTxn<&Env, ()>, u64, u64, UP<u64, u64>>(&mut txn).unwrap();

[3.413]

[3.12694]

let env = Env::new_anon(409_600_000, 1).unwrap();
let mut txn = Env::mut_txn_begin(&env).unwrap();
let mut db2 = create_db_::<MutTxn<&Env, ()>, u64, u64, UP<u64, u64>>(&mut txn).unwrap();
edit in sanakirja/src/tests.rs at line 514

[3.12738]

[3.12762]

let n = 1_000u64;
replacement in sanakirja/src/tests.rs at line 516

[3.12782]→[3.442:489](∅→∅),[3.489]→[3.2434:2492](∅→∅)

debug!("=================== {:?}", i);
assert!(put(&mut txn, &mut db, &i, &i).unwrap());

[3.12782]

[3.12831]

assert!(put(&mut txn, &mut db2, &i, &i).unwrap());
replacement in sanakirja/src/tests.rs at line 521

[3.604]→[3.604:651](∅→∅),[3.651]→[3.2856:2899](∅→∅)

debug!("=================== {:?}", i);
get(&txn, &db, &i, None).unwrap();

[3.604]

[3.701]

get(&txn, &db2, &i, None).unwrap();
replacement in sanakirja/src/tests.rs at line 524

[3.760]→[3.2733:3005](∅→∅)

println!("unsized length = {:?}", (txn.length >> 12) - len);
add_refs(&txn, &db, &mut refs).unwrap();
for (p, r) in refs.iter() {
if *r >= 2 {
error!("{:?} referenced twice", p);
err += 1
}
}
assert_eq!(err, 0);

[3.760]

[2.1136]

refs.clear();
add_refs(&txn, &db2, &mut refs).unwrap();
add_free_refs_mut(&mut txn, &mut refs).unwrap();
edit in sanakirja/src/lib.rs at line 13

[18.2979]

[3.3592]

//!
//! Here's an example of how to use it (starting with 64 pages, 2
//! versions, see below for details about what that means). The file
//! grows automatically, as needed.
//!
//! ```
//! use sanakirja::*;
//! let dir = tempfile::tempdir().unwrap();
//! let path = dir.path().join("db");
//! let env = Env::new(&path, 1 << 20, 2).unwrap();
//! let mut txn = Env::mut_txn_begin(&env).unwrap();
//! let mut db = btree::create_db::<_, u64, u64>(&mut txn).unwrap();
//! for i in 0..100_000u64 {
//! btree::put(&mut txn, &mut db, &i, &(i*i)).unwrap();
//! }
//! let root_db = 0;
//! txn.set_root(root_db, db.db);
//! txn.commit().unwrap();
//! let txn = Env::txn_begin(&env).unwrap();
//! let db: btree::Db<u64, u64> = txn.root_db(root_db).unwrap();
//! assert_eq!(btree::get(&txn, &db, &50_000, None).unwrap(), Some((&50_000, &(50_000 * 50_000))));
//! for entry in btree::iter(&txn, &db, None).unwrap() {
//! let (k, v) = entry.unwrap();
//! assert_eq!(*k * *k, *v)
//! }
//! ```
replacement in sanakirja/src/environment/muttxn.rs at line 30

[3.15982]→[3.27437:27473](∅→∅),[3.7288]→[3.27437:27473](∅→∅),[3.1320]→[3.27437:27473](∅→∅)

rc: Option<btree::Db<u64, ()>>,

[3.7288]

[3.7289]

pub(crate) rc: Option<btree::Db<u64, ()>>,
edit in sanakirja/src/debug.rs at line 158

[2.3071]

[2.3071]

} else if txn.free_owned_pages.iter().any(|x| *x == page) {
continue;
} else if txn.free_pages.iter().any(|x| *x == page) {
continue;
replacement in sanakirja/src/debug.rs at line 260

[2.6299]→[2.6299:6901](∅→∅)

let env = txn.env.borrow();
unsafe {
let p = &*(env.mmaps.lock()[0].ptr.add(txn.root * PAGE_SIZE)
as *const crate::environment::GlobalHeader);
if p.free_db != 0 {
debug!("add_free_refs: free = 0x{:x}", p.free_db);
let free_db: Db<u64, ()> = btree::Db::from_page(p.free_db);
add_refs(txn, &free_db, pages)?;
}
if p.rc_db != 0 {
debug!("add_free_refs: rc = 0x{:x}", p.rc_db);
let rc_db: Db<u64, ()> = btree::Db::from_page(p.rc_db);
add_refs(txn, &rc_db, pages)?;
}
};

[2.6299]

[2.6901]

if txn.free != 0 {
debug!("add_free_refs: free = 0x{:x}", txn.free);
let free_db: Db<u64, ()> = btree::Db::from_page(txn.free);
add_refs(txn, &free_db, pages)?;
}
if let Some(ref rc) = txn.rc {
debug!("add_free_refs: rc = 0x{:x}", rc.db);
add_refs(txn, &rc, pages)?;
}
replacement in sanakirja/Cargo.toml at line 3

[3.108441]→[3.0:18](∅→∅)

version = "1.0.0"

[3.108441]

[3.108459]

version = "1.0.1"