sync db: postcard

This commit is contained in:
Dmitry Belyaev 2023-08-23 21:40:07 +03:00
parent 1d4005abdb
commit 7e6b513179
1 changed files with 31 additions and 30 deletions

View File

@ -6,13 +6,13 @@ use std::{
sync::Arc,
};
use serde::{de::DeserializeOwned, Serialize};
use memmap::{Mmap, MmapOptions};
type LSize = u32;
const LEN_SIZE: usize = std::mem::size_of::<LSize>();
const BINCODE_CFG: bincode::config::Configuration = bincode::config::standard();
use crate::util::BincodeVecWriter;
use crate::util::ErrorToString;
pub struct WriterOpts {
@ -28,19 +28,19 @@ impl Default for WriterOpts {
compress_lvl: 1,
data_buf_size: 500 * 1024 * 1024,
out_buf_size: 200 * 1024 * 1024,
current_buf_size: 100 * 1024,
current_buf_size: 20 * 1024,
}
}
}
pub struct Writer<T>
where
T: bincode::Encode,
T: Serialize,
{
out: io::BufWriter<fs::File>,
data_buf: Cursor<Vec<u8>>,
cur_buf_raw: Cursor<Vec<u8>>,
cur_buf_item: BincodeVecWriter,
cur_buf_item: Vec<u8>,
table: Vec<LSize>,
compress_lvl: i32,
_t: PhantomData<Arc<T>>,
@ -48,7 +48,7 @@ where
impl<T> Writer<T>
where
T: bincode::Encode,
T: Serialize,
{
pub fn new<P: AsRef<Path>>(path: P, opts: WriterOpts) -> Result<Self, String> {
let out = fs::File::create(path).str_err()?;
@ -58,8 +58,7 @@ where
let cur_buf_raw: Vec<u8> = Vec::with_capacity(opts.current_buf_size);
let cur_buf_raw = Cursor::new(cur_buf_raw);
let cur_buf_item: Vec<u8> = Vec::with_capacity(opts.current_buf_size);
let cur_buf_item = BincodeVecWriter::new(cur_buf_item);
let cur_buf_item: Vec<u8> = vec![0; opts.current_buf_size];
let compress_lvl = opts.compress_lvl;
@ -83,19 +82,20 @@ where
pub fn push_by_ref(&mut self, item: &T) -> Result<(), String> {
let pos: LSize = self.data_buf.position() as LSize;
bincode::encode_into_writer(item, &mut self.cur_buf_item, BINCODE_CFG).str_err()?;
let cur_item_data = postcard::to_slice(item, self.cur_buf_item.as_mut_slice()).str_err()?;
let mut zencoder = zstd::stream::raw::Encoder::new(self.compress_lvl).str_err()?;
zencoder
.set_pledged_src_size(Some(self.cur_buf_item.len() as u64))
.set_pledged_src_size(Some(cur_item_data.len() as u64))
.str_err()?;
self.cur_buf_raw.set_position(0);
let mut cur_buf_z = zstd::stream::zio::Writer::new(&mut self.cur_buf_raw, zencoder);
cur_buf_z.write_all(&self.cur_buf_item).str_err()?;
cur_buf_z.write_all(cur_item_data).str_err()?;
cur_buf_z.finish().str_err()?;
cur_buf_z.flush().str_err()?;
self.cur_buf_item.clear();
cur_item_data.fill(0);
self.table.push(pos);
let (cur_buf_raw, _) = cur_buf_z.into_inner();
@ -150,7 +150,7 @@ where
pub struct Reader<T>
where
T: bincode::Decode,
T: DeserializeOwned,
{
mmap: Mmap,
count: usize,
@ -160,7 +160,7 @@ where
impl<T> Reader<T>
where
T: bincode::Decode,
T: DeserializeOwned,
{
pub fn new<P: AsRef<Path>>(path: P, _buf_size: usize) -> Result<Self, String> {
let file = fs::File::open(path).str_err()?;
@ -215,9 +215,9 @@ where
let data = zstd::decode_all(reader).str_err()?;
// decode item
let item: (T, usize) = bincode::decode_from_slice(&data, BINCODE_CFG).str_err()?;
let (item, _): (T, _) = postcard::take_from_bytes(&data).str_err()?;
Ok(item.0)
Ok(item)
}
pub fn iter(&self) -> ReaderIter<'_, T> {
@ -227,7 +227,7 @@ where
pub struct ReaderIter<'a, T>
where
T: bincode::Decode,
T: DeserializeOwned,
{
reader: &'a Reader<T>,
index: Option<usize>,
@ -235,7 +235,7 @@ where
impl<'a, T> ReaderIter<'a, T>
where
T: bincode::Decode,
T: DeserializeOwned,
{
fn new(reader: &'a Reader<T>) -> Self {
ReaderIter {
@ -247,7 +247,7 @@ where
impl<'a, T> Iterator for ReaderIter<'a, T>
where
T: bincode::Decode,
T: DeserializeOwned,
{
type Item = T;
@ -300,7 +300,7 @@ where
impl<'a, T> ExactSizeIterator for ReaderIter<'a, T>
where
T: bincode::Decode,
T: DeserializeOwned,
{
fn len(&self) -> usize {
self.reader.len()
@ -309,7 +309,7 @@ where
pub struct ReaderIntoIter<T>
where
T: bincode::Decode,
T: DeserializeOwned,
{
reader: Reader<T>,
index: Option<usize>,
@ -317,7 +317,7 @@ where
impl<T> ReaderIntoIter<T>
where
T: bincode::Decode,
T: DeserializeOwned,
{
fn new(reader: Reader<T>) -> Self {
Self {
@ -329,7 +329,7 @@ where
impl<T> Iterator for ReaderIntoIter<T>
where
T: bincode::Decode,
T: DeserializeOwned,
{
type Item = T;
@ -382,7 +382,7 @@ where
impl<T> ExactSizeIterator for ReaderIntoIter<T>
where
T: bincode::Decode,
T: DeserializeOwned,
{
fn len(&self) -> usize {
self.reader.len()
@ -391,7 +391,7 @@ where
impl<T> IntoIterator for Reader<T>
where
T: bincode::Decode,
T: DeserializeOwned,
{
type Item = T;
type IntoIter = ReaderIntoIter<Self::Item>;
@ -404,9 +404,10 @@ where
#[cfg(test)]
mod test {
use super::*;
use serde::Deserialize;
use tempfile::tempdir;
#[derive(bincode::Encode, bincode::Decode, Clone, Debug, PartialEq, Eq, PartialOrd, Ord)]
#[derive(Serialize, Deserialize, Clone, Debug, PartialEq, Eq, PartialOrd, Ord)]
struct TestData {
num: u64,
test: String,
@ -427,7 +428,7 @@ mod test {
compress_lvl: 1,
data_buf_size: 10 * 1024 * 1024,
out_buf_size: 10 * 1024 * 1024,
current_buf_size: 4096,
current_buf_size: 20 * 1024,
};
let mut writer: Writer<TestData> = Writer::new(&tmpfile, opts).expect("new writer");
@ -454,7 +455,7 @@ mod test {
compress_lvl: 1,
data_buf_size: 10 * 1024 * 1024,
out_buf_size: 10 * 1024 * 1024,
current_buf_size: 4096,
current_buf_size: 20 * 1024,
};
let mut writer: Writer<TestData> = Writer::new(&tmpfile, opts).expect("new writer");
@ -480,7 +481,7 @@ mod test {
compress_lvl: 1,
data_buf_size: 10 * 1024 * 1024,
out_buf_size: 10 * 1024 * 1024,
current_buf_size: 4096,
current_buf_size: 20 * 1024,
};
let mut writer: Writer<TestData> = Writer::new(&tmpfile, opts).expect("new writer");
@ -509,7 +510,7 @@ mod test {
compress_lvl: 1,
data_buf_size: 10 * 1024 * 1024,
out_buf_size: 10 * 1024 * 1024,
current_buf_size: 4096,
current_buf_size: 20 * 1024,
};
let mut writer: Writer<TestData> = Writer::new(&tmpfile, opts).expect("new writer");