Add debug log that shows up in trace whenever CacheLoader#load is invoked

This allows us to see cache misses in the trace.

Change-Id: I7ed1c779c35e6621cabaa6f257289913c92e1fe9
Signed-off-by: Edwin Kempin <ekempin@google.com>

java/com/google/gerrit/server/account/AccountCacheImpl.java

@@ -179,6 +179,7 @@ public class AccountCacheImpl implements AccountCache {
 
     @Override
     public Optional<AccountState> load(Account.Id who) throws Exception {
+      logger.atFine().log("Loading account %s", who);
       return accounts.get(who);
     }
   }

java/com/google/gerrit/server/account/GroupCacheImpl.java

@@ -144,6 +144,7 @@ public class GroupCacheImpl implements GroupCache {
 
     @Override
     public Optional<InternalGroup> load(AccountGroup.Id key) throws Exception {
+      logger.atFine().log("Loading group %s by ID", key);
       return groupQueryProvider.get().byId(key);
     }
   }
@@ -158,6 +159,7 @@ public class GroupCacheImpl implements GroupCache {
 
     @Override
     public Optional<InternalGroup> load(String name) throws Exception {
+      logger.atFine().log("Loading group '%s' by name", name);
       return groupQueryProvider.get().byName(new AccountGroup.NameKey(name));
     }
   }
@@ -172,6 +174,7 @@ public class GroupCacheImpl implements GroupCache {
 
     @Override
     public Optional<InternalGroup> load(String uuid) throws Exception {
+      logger.atFine().log("Loading group %s by UUID", uuid);
       return groups.getGroup(new AccountGroup.UUID(uuid));
     }
   }

java/com/google/gerrit/server/account/GroupIncludeCacheImpl.java

@@ -148,6 +148,7 @@ public class GroupIncludeCacheImpl implements GroupIncludeCache {
 
     @Override
     public ImmutableSet<AccountGroup.UUID> load(Account.Id memberId) throws OrmException {
+      logger.atFine().log("Loading groups with member %s", memberId);
       return groupQueryProvider
           .get()
           .byMember(memberId)
@@ -168,6 +169,7 @@ public class GroupIncludeCacheImpl implements GroupIncludeCache {
 
     @Override
     public ImmutableList<AccountGroup.UUID> load(AccountGroup.UUID key) throws OrmException {
+      logger.atFine().log("Loading parent groups of %s", key);
       return groupQueryProvider
           .get()
           .bySubgroup(key)
@@ -187,6 +189,7 @@ public class GroupIncludeCacheImpl implements GroupIncludeCache {
 
     @Override
     public ImmutableList<AccountGroup.UUID> load(String key) throws Exception {
+      logger.atFine().log("Loading all external groups");
       return groups.getExternalGroups().collect(toImmutableList());
     }
   }

java/com/google/gerrit/server/account/externalids/ExternalIdCacheImpl.java

@@ -152,6 +152,7 @@ class ExternalIdCacheImpl implements ExternalIdCache {
 
     @Override
     public AllExternalIds load(ObjectId notesRev) throws Exception {
+      logger.atFine().log("Loading external IDs (revision=%s)", notesRev);
       Multimap<Account.Id, ExternalId> extIdsByAccount =
           MultimapBuilder.hashKeys().arrayListValues().build();
       for (ExternalId extId : externalIdReader.all(notesRev)) {

java/com/google/gerrit/server/auth/ldap/LdapRealm.java

@@ -351,6 +351,7 @@ class LdapRealm extends AbstractRealm {
 
     @Override
     public Optional<Account.Id> load(String username) throws Exception {
+      logger.atFine().log("Loading account for username %s", username);
       return externalIds
           .get(ExternalId.Key.create(SCHEME_GERRIT, username))
           .map(ExternalId::accountId);
@@ -367,6 +368,7 @@ class LdapRealm extends AbstractRealm {
 
     @Override
     public Set<AccountGroup.UUID> load(String username) throws Exception {
+      logger.atFine().log("Loading group for member with username %s", username);
       final DirContext ctx = helper.open();
       try {
         return helper.queryForGroups(ctx, username, null);
@@ -386,6 +388,7 @@ class LdapRealm extends AbstractRealm {
 
     @Override
     public Boolean load(String groupDn) throws Exception {
+      logger.atFine().log("Loading groupDn %s", groupDn);
       final DirContext ctx = helper.open();
       try {
         Name compositeGroupName = new CompositeName().add(groupDn);

java/com/google/gerrit/server/cache/h2/H2CacheImpl.java

@@ -235,6 +235,8 @@ public class H2CacheImpl<K, V> extends AbstractLoadingCache<K, V> implements Per
 
     @Override
     public ValueHolder<V> load(K key) throws Exception {
+      logger.atFine().log("Loading value for %s from cache", key);
+
       if (store.mightContain(key)) {
         ValueHolder<V> h = store.getIfPresent(key);
         if (h != null) {

java/com/google/gerrit/server/git/SearchingChangeCacheImpl.java

@@ -144,6 +144,7 @@ public class SearchingChangeCacheImpl implements GitReferenceUpdatedListener {
 
     @Override
     public List<CachedChange> load(Project.NameKey key) throws Exception {
+      logger.atFine().log("Loading changes of project %s", key);
       try (ManualRequestContext ctx = requestContext.open()) {
         List<ChangeData> cds =
             queryProvider

java/com/google/gerrit/server/project/ProjectCacheImpl.java

@@ -269,6 +269,7 @@ public class ProjectCacheImpl implements ProjectCache {
 
     @Override
     public ProjectState load(String projectName) throws Exception {
+      logger.atFine().log("Loading project %s", projectName);
       long now = clock.read();
       Project.NameKey key = new Project.NameKey(projectName);
       try (Repository git = mgr.openRepository(key)) {
@@ -298,6 +299,7 @@ public class ProjectCacheImpl implements ProjectCache {
 
     @Override
     public ImmutableSortedSet<Project.NameKey> load(ListKey key) throws Exception {
+      logger.atFine().log("Loading project list");
       return ImmutableSortedSet.copyOf(mgr.list());
     }
   }

java/com/google/gerrit/sshd/SshKeyCacheImpl.java

@@ -102,6 +102,8 @@ public class SshKeyCacheImpl implements SshKeyCache {
 
     @Override
     public Iterable<SshKeyCacheEntry> load(String username) throws Exception {
+      logger.atFine().log("Loading SSH keys for account with username %s", username);
+
       Optional<ExternalId> user = externalIds.get(ExternalId.Key.create(SCHEME_USERNAME, username));
       if (!user.isPresent()) {
         return NO_SUCH_USER;