From 6c865d26fd557c232ad8372bda9de2eecc25d65e Mon Sep 17 00:00:00 2001
From: teddy <teddy.kim.kim@tf.dabeeo.com>
Date: Thu, 12 Feb 2026 18:18:44 +0900
Subject: [PATCH] =?UTF-8?q?=EC=9E=84=EC=8B=9C=ED=8C=8C=EC=9D=BC=EC=83=9D?=
 =?UTF-8?q?=EC=84=B1=20=EC=86=8C=ED=94=84=ED=8A=B8=EB=A7=81=ED=81=AC?=
 =?UTF-8?q?=EC=97=90=EC=84=9C=20=ED=95=98=EB=93=9C=EB=A7=81=ED=81=AC?=
 =?UTF-8?q?=EB=A1=9C=20=EB=B3=80=EA=B2=BD?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 .../model/service/TmpDatasetService.java      | 65 ++++++++++++++-----
 1 file changed, 50 insertions(+), 15 deletions(-)

diff --git a/src/main/java/com/kamco/cd/training/model/service/TmpDatasetService.java b/src/main/java/com/kamco/cd/training/model/service/TmpDatasetService.java
index 7f04c98..918bc77 100644
--- a/src/main/java/com/kamco/cd/training/model/service/TmpDatasetService.java
+++ b/src/main/java/com/kamco/cd/training/model/service/TmpDatasetService.java
@@ -18,7 +18,7 @@ public class TmpDatasetService {
 
   public String buildTmpDatasetSymlink(String uid, List<String> datasetUids) throws IOException {
 
-    log.info("========== buildTmpDatasetSymlink START ==========");
+    log.info("========== buildTmpDatasetHardlink START ==========");
     log.info("uid={}", uid);
     log.info("datasetUids={}", datasetUids);
     log.info("requestDir(raw)={}", requestDir);
@@ -30,8 +30,9 @@ public class TmpDatasetService {
     log.info("BASE exists? {}", Files.isDirectory(BASE));
     log.info("tmp={}", tmp);
 
-    long noDir = 0, scannedDirs = 0, regularFiles = 0, symlinksMade = 0;
+    long noDir = 0, scannedDirs = 0, regularFiles = 0, hardlinksMade = 0;
 
+    // tmp 디렉토리 준비
     for (String type : List.of("train", "val")) {
       for (String part : List.of("input1", "input2", "label")) {
         Path dir = tmp.resolve(type).resolve(part);
@@ -40,6 +41,27 @@ public class TmpDatasetService {
       }
     }
 
+    // 하드링크는 "같은 파일시스템"에서만 가능하므로 BASE/tmp가 같은 FS인지 미리 확인(권장)
+    try {
+      var baseStore = Files.getFileStore(BASE);
+      var tmpStore = Files.getFileStore(tmp.getParent()); // BASE/tmp
+      if (!baseStore.name().equals(tmpStore.name()) || !baseStore.type().equals(tmpStore.type())) {
+        throw new IOException(
+            "Hardlink requires same filesystem. baseStore="
+                + baseStore.name()
+                + "("
+                + baseStore.type()
+                + "), tmpStore="
+                + tmpStore.name()
+                + "("
+                + tmpStore.type()
+                + ")");
+      }
+    } catch (Exception e) {
+      // FileStore 비교가 환경마다 애매할 수 있어서, 여기서는 경고만 주고 실제 createLink에서 최종 판단하게 둘 수도 있음.
+      log.warn("FileStore check skipped/failed (will rely on createLink): {}", e.toString());
+    }
+
     for (String id : datasetUids) {
       Path srcRoot = BASE.resolve(id);
       log.info("---- dataset id={} srcRoot={} exists? {}", id, srcRoot, Files.isDirectory(srcRoot));
@@ -70,18 +92,21 @@ public class TmpDatasetService {
               String dstName = id + "__" + f.getFileName();
               Path dst = tmp.resolve(type).resolve(part).resolve(dstName);
 
+              // dst가 남아있으면 삭제(심볼릭링크든 파일이든)
+              if (Files.exists(dst) || Files.isSymbolicLink(dst)) {
+                Files.delete(dst);
+                log.debug("deleted existing: {}", dst);
+              }
+
               try {
-                if (Files.exists(dst) || Files.isSymbolicLink(dst)) {
-                  Files.delete(dst);
-                  log.debug("deleted existing: {}", dst);
-                }
-
-                Files.createSymbolicLink(dst, f.toAbsolutePath());
-                symlinksMade++;
-                log.debug("created symlink: {} -> {}", dst, f.toAbsolutePath());
-
-              } catch (Exception e) {
-                log.error("FAILED create symlink: {} -> {}", dst, f.toAbsolutePath(), e);
+                // 하드링크 생성 (dst가 새 파일로 생기지만 inode는 f와 동일)
+                Files.createLink(dst, f);
+                hardlinksMade++;
+                log.debug("created hardlink: {} => {}", dst, f);
+              } catch (IOException e) {
+                // 여기서 바로 실패시키면 “tmp는 만들었는데 내용은 0개” 같은 상태를 방지할 수 있음
+                log.error("FAILED create hardlink: {} => {}", dst, f, e);
+                throw e;
               }
             }
           }
@@ -89,13 +114,23 @@ public class TmpDatasetService {
       }
     }
 
+    if (hardlinksMade == 0) {
+      throw new IOException(
+          "No hardlinks created. regularFiles="
+              + regularFiles
+              + ", scannedDirs="
+              + scannedDirs
+              + ", noDir="
+              + noDir);
+    }
+
     log.info("tmp dataset created: {}", tmp);
     log.info(
-        "summary: scannedDirs={}, noDir={}, regularFiles={}, symlinksMade={}",
+        "summary: scannedDirs={}, noDir={}, regularFiles={}, hardlinksMade={}",
         scannedDirs,
         noDir,
         regularFiles,
-        symlinksMade);
+        hardlinksMade);
 
     return uid;
   }