[None][fix] Pass mode & directory

[tshmilnvidia]

Passing mode & directory parameters to relevant onboard & offload functions.

Summary by CodeRabbit

• New Features

  • Users can specify KV‑cache transfer mode and optional directory when loading, allocating, onboarding, or offloading cache blocks; generation requests expose these settings.

• Bug Fixes

  • Transfer mode and directory are now consistently passed through block management and transfer flows.

• Chores

  • Directory accessor return changed to a const‑reference to avoid unnecessary copies (public API update).

[coderabbitai]

📝 Walkthrough

Walkthrough

Adds optional KV-cache transfer mode and directory parameters to block-management APIs and GenerationRequest accessors, and changes KvCacheRetentionConfig::getDirectory() to return a const reference; parameters are threaded through WindowBlockManager, BlockManager, and transfer-manager call sites without altering core logic.

Changes

Cohort / File(s)	Change Summary
Batch manager headers cpp/include/tensorrt_llm/batch_manager/kvCacheManager.h	Extended public signatures in WindowBlockManager and BlockManager to accept executor::KvCacheTransferMode mode = DRAM and std::optional<std::string> directory = std::nullopt. Added GenerationRequest::getTransferMode() and GenerationRequest::getDirectory() accessors (returns const&).
Batch manager implementation cpp/tensorrt_llm/batch_manager/kvCacheManager.cpp	Threaded mode and directory through implementations and call sites: getFreeBlock, loadOrAllocateBlocks, onboardBlock, offloadBlock, allocation/replacement helpers, and calls into the transfer manager; behavior unchanged aside from parameter passing.
Executor header cpp/include/tensorrt_llm/executor/executor.h	Changed KvCacheRetentionConfig::getDirectory() return type from std::optional<std::string> (by value) to const std::optional<std::string>&.
Executor implementation cpp/tensorrt_llm/executor/kvCacheRetentionConfig.cpp	Updated implementation to return mDirectory by const& to match the header change.

Sequence Diagram(s)

sequenceDiagram
    participant Client
    participant BlockManager
    participant WindowBlockManager
    participant TransferManager

    Client->>BlockManager: onboardBlock(block, windowSize, mode, directory)
    BlockManager->>WindowBlockManager: onboardBlock(block, windowSize, mode, directory)
    WindowBlockManager->>WindowBlockManager: getFreeBlock(..., mode, directory)
    WindowBlockManager->>TransferManager: onboard(block, mode, directory)

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sequenceDiagram
    participant Client
    participant BlockManager
    participant WindowBlockManager
    participant TransferManager

    Client->>BlockManager: offloadBlock(block, windowSize, mode, directory)
    BlockManager->>WindowBlockManager: offloadBlock(block, windowSize, mode, directory)
    WindowBlockManager->>TransferManager: offload(block, 0, mode, directory)

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Estimated code review effort

🎯 3 (Moderate) | ⏱️ ~20 minutes

Suggested reviewers

• pcastonguay
• chuangz0
• Shixiaowei02
• Tabrizian
• nv-guomingz

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📥 Commits

Reviewing files that changed from the base of the PR and between 079ae7d and 58a1aac.

📒 Files selected for processing (4)

• cpp/include/tensorrt_llm/batch_manager/kvCacheManager.h (5 hunks)
• cpp/include/tensorrt_llm/executor/executor.h (1 hunks)
• cpp/tensorrt_llm/batch_manager/kvCacheManager.cpp (13 hunks)
• cpp/tensorrt_llm/executor/kvCacheRetentionConfig.cpp (1 hunks)

👮 Files not reviewed due to content moderation or server errors (4)

• cpp/include/tensorrt_llm/executor/executor.h
• cpp/tensorrt_llm/executor/kvCacheRetentionConfig.cpp
• cpp/include/tensorrt_llm/batch_manager/kvCacheManager.h
• cpp/tensorrt_llm/batch_manager/kvCacheManager.cpp

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Files:

• cpp/include/tensorrt_llm/executor/executor.h
• cpp/tensorrt_llm/executor/kvCacheRetentionConfig.cpp
• cpp/include/tensorrt_llm/batch_manager/kvCacheManager.h
• cpp/tensorrt_llm/batch_manager/kvCacheManager.cpp

**/*.{h,hpp,hxx,hh,cuh,cpp,cxx,cc,cu}

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Parameter names must be consistent between declarations and definitions

Files:

• cpp/include/tensorrt_llm/executor/executor.h
• cpp/tensorrt_llm/executor/kvCacheRetentionConfig.cpp
• cpp/include/tensorrt_llm/batch_manager/kvCacheManager.h
• cpp/tensorrt_llm/batch_manager/kvCacheManager.cpp

**/*.{h,hpp,hxx,hh,cuh}

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Header files must use include guards named TRTLLM__H without underscores prefix/suffix (e.g., TRTLLM_FOO_BAR_HELLO_H)

Files:

• cpp/include/tensorrt_llm/executor/executor.h
• cpp/include/tensorrt_llm/batch_manager/kvCacheManager.h

**/*.{cpp,cxx,cc,cu,h,hpp,hxx,hh,cuh,py}

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Prepend NVIDIA copyright header (current year) to all source files

Files:

• cpp/include/tensorrt_llm/executor/executor.h
• cpp/tensorrt_llm/executor/kvCacheRetentionConfig.cpp
• cpp/include/tensorrt_llm/batch_manager/kvCacheManager.h
• cpp/tensorrt_llm/batch_manager/kvCacheManager.cpp

**/*.{cpp,cxx,cc,cu}

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**/*.{cpp,cxx,cc,cu}: Avoid literal values except for 0, nullptr, true, false; use named constexpr for other literals
Place semicolon of empty for/while loop on a new line
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Switch on enums should enumerate all values and omit default to catch new values at compile time
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Prefer anonymous namespaces over static for internal linkage of functions
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Files:

• cpp/tensorrt_llm/executor/kvCacheRetentionConfig.cpp
• cpp/tensorrt_llm/batch_manager/kvCacheManager.cpp

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[Shixiaowei02]

const std::optional<std::string>& is better.

[Shixiaowei02]

Could this also be included in the test, please? Thank you.

[glevnv]

Could this also be included in the test, please? Thank you.

Done

[bo-nv]

Could this also be included in the test, please? Thank you.

Done

IIUC, we already have these changes in #5488. can we close this one? @glevnv

[tshmilnvidia]

@bo-nv Closing this one, included in #5488