rust/neon
1
0
Fork 0
mirror of https://github.com/neondatabase/neon.git synced 2026-06-04 22:10:39 +00:00
Code Issues Packages Projects Releases Wiki Activity

Add 'dump_layerfile' utility for debugging.

Browse Source 
Seems handy for getting a quick idea of what's stored in an
image or delta layer file.

Example output on a file after runnnig pgbench for a while:

    % ./target/debug/dump_layerfile pgbench_layers/pg_control_checkpoint_0_00000000016B914A
    ----- image layer for checkpoint.0 at 0/16B914A ----
    non-blocky (88 bytes)
    % ./target/debug/dump_layerfile pgbench_layers/pg_xact_0000_0_000000000412FD40
    ----- image layer for pg_xact/0000.0 at 0/412FD40 ----
    (1) blocks
    % ./target/debug/dump_layerfile pgbench_layers/rel_1663_14236_1247_0_0_00000000016B914A_000000000412FD40 | head -n 20
    ----- delta layer for 1663/14236/1247.0 0/16B914A-0/412FD40 ----
    --- relsizes ---
      0/16B914A: 14
      0/16CA559: 15
    --- page versions ---
      blk 13 at 0/16BB1D2:  rec 8162 bytes will_init: true HEAP INSERT
      blk 14 at 0/16CA559:  rec 8241 bytes will_init: true XLOG FPI
      blk 14 at 0/16CA637:  rec 215 bytes will_init: true HEAP INSERT
      blk 14 at 0/16DF14F:  rec 215 bytes will_init: false HEAP INSERT
      blk 14 at 0/16DF3A7:  rec 215 bytes will_init: false HEAP INSERT
      blk 14 at 0/16E0637:  rec 215 bytes will_init: false HEAP INSERT
      blk 14 at 0/16E088F:  rec 215 bytes will_init: false HEAP INSERT
      blk 14 at 0/16E5F9F:  rec 215 bytes will_init: false HEAP INSERT
      blk 14 at 0/16E620F:  rec 215 bytes will_init: false HEAP INSERT
This commit is contained in:
Heikki Linnakangas
2021-08-27 21:10:17 +03:00
committed by Patrick Insinger
parent 5ac3cb1c72
commit d7bebd8074
9 changed files with 295 additions and 50 deletions
Download Patch File Download Diff File Expand all files Collapse all files

68
pageserver/src/waldecoder.rs
View File

@@ -965,3 +965,71 @@ pub fn decode_wal_record(record: Bytes) -> DecodedWALRecord {
main_data_offset,
}
}
///
/// Build a human-readable string to describe a WAL record
///
/// For debugging purposes
pub fn describe_wal_record(record: &Bytes) -> String {
// TODO: It would be nice to use the PostgreSQL rmgrdesc infrastructure for this.
// Maybe use the postgres wal redo process, the same used for replaying WAL records?
// Or could we compile the rmgrdesc routines into the dump_layer_file() binary directly,
// without worrying about security?
//
// But for now, we have a hand-written code for a few common WAL record types here.
let mut buf = record.clone();
// 1. Parse XLogRecord struct
// FIXME: assume little-endian here
let xlogrec = XLogRecord::from_bytes(&mut buf);
let unknown_str: String;
let result: &str = match xlogrec.xl_rmid {
pg_constants::RM_HEAP2_ID => {
let info = xlogrec.xl_info & pg_constants::XLOG_HEAP_OPMASK;
match info {
pg_constants::XLOG_HEAP2_MULTI_INSERT => "HEAP2 MULTI_INSERT",
pg_constants::XLOG_HEAP2_VISIBLE => "HEAP2 VISIBLE",
_ => {
unknown_str = format!("HEAP2 UNKNOWN_0x{:02x}", info);
&unknown_str
}
}
}
pg_constants::RM_HEAP_ID => {
let info = xlogrec.xl_info & pg_constants::XLOG_HEAP_OPMASK;
match info {
pg_constants::XLOG_HEAP_INSERT => "HEAP INSERT",
pg_constants::XLOG_HEAP_DELETE => "HEAP DELETE",
pg_constants::XLOG_HEAP_UPDATE => "HEAP UPDATE",
pg_constants::XLOG_HEAP_HOT_UPDATE => "HEAP HOT_UPDATE",
_ => {
unknown_str = format!("HEAP2 UNKNOWN_0x{:02x}", info);
&unknown_str
}
}
}
pg_constants::RM_XLOG_ID => {
let info = xlogrec.xl_info & pg_constants::XLR_RMGR_INFO_MASK;
match info {
pg_constants::XLOG_FPI => "XLOG FPI",
pg_constants::XLOG_FPI_FOR_HINT => "XLOG FPI_FOR_HINT",
_ => {
unknown_str = format!("XLOG UNKNOWN_0x{:02x}", info);
&unknown_str
}
}
}
rmid => {
let info = xlogrec.xl_info & pg_constants::XLR_RMGR_INFO_MASK;
unknown_str = format!("UNKNOWN_RM_{} INFO_0x{:02x}", rmid, info);
&unknown_str
}
};
String::from(result)
}