thevar1able/ClickHouse
1
0
Fork 0
mirror of https://github.com/ClickHouse/ClickHouse.git synced 2024-11-23 08:02:02 +00:00
Code Issues Packages Projects Releases Wiki Activity

Merge pull request #57970 from ClickHouse/nickitat-patch-17

Browse Source 
Always use `pread` for reading cache segments
This commit is contained in:
Alexey Milovidov 2023-12-17 20:53:05 +01:00 committed by GitHub
commit dbd509417e
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23
1 changed files with 3 additions and 12 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

15
src/Disks/IO/CachedOnDiskReadBufferFromFile.cpp
View File

@ -177,22 +177,13 @@ CachedOnDiskReadBufferFromFile::getCacheReadBuffer(const FileSegment & file_segm
}
ReadSettings local_read_settings{settings};
local_read_settings.local_fs_prefetch = false;
if (local_read_settings.local_fs_method != LocalFSReadMethod::pread_threadpool)
local_read_settings.local_fs_method = LocalFSReadMethod::pread;
local_read_settings.local_fs_method = LocalFSReadMethod::pread;
if (use_external_buffer)
local_read_settings.local_fs_buffer_size = 0;
cache_file_reader = createReadBufferFromFileBase(
path,
local_read_settings,
std::nullopt,
std::nullopt,
file_segment.getFlagsForLocalRead(),
/*existing_memory=*/nullptr,
/*alignment=*/0,
/*use_external_buffer=*/true);
cache_file_reader
= createReadBufferFromFileBase(path, local_read_settings, std::nullopt, std::nullopt, file_segment.getFlagsForLocalRead());
if (getFileSizeFromReadBuffer(*cache_file_reader) == 0)
throw Exception(ErrorCodes::LOGICAL_ERROR, "Attempt to read from an empty cache file: {}", path);