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Fixed a few important bugs.
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1. Fixes a problem where blcoks with zero tuples were being written out. This
   could occur when, say 200 blcoks would be queued for eviction, but only 50
   blocks worth of data could be evicted. Then it would still evict 150 empty
   blocks due to an = sign.
2. Fixed a double delete of blockIDs when migrating that caused a problem due
   to running out of room.
3. Moved the chooseDB selection of AntiCacheDBs to inside the loop of batching
   evictions. By having it outside of the loop, when a tier would fill, it
   wouldn't trigger a migration, only a FullBackingStoreException and failure.
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user committed Jun 22, 2015
1 parent 164f61c commit 17fe61d
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Showing 3 changed files with 21 additions and 14 deletions.
2 changes: 1 addition & 1 deletion src/ee/anticache/AntiCacheDB.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -82,7 +82,7 @@ AntiCacheBlock* AntiCacheDB::getLRUBlock() {
} else {
lru_block_id = m_block_lru.front();
lru_block = readBlock(lru_block_id);
m_totalBlocks--;
//m_totalBlocks--;
return lru_block;
}
}
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25 changes: 15 additions & 10 deletions src/ee/anticache/AntiCacheEvictionManager.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -549,11 +549,7 @@ bool AntiCacheEvictionManager::evictBlockToDisk(PersistentTable *table, const lo
VOLT_DEBUG("%s Table Schema:\n%s",
evictedTable->name().c_str(), evictedTable->schema()->debug().c_str());

// get the AntiCacheDB instance from the executorContext
// For now use the single AntiCacheDB from PersistentTable but in the future, this
// method to get the AntiCacheDB will have to choose which AntiCacheDB from to
// evict to
AntiCacheDB* antiCacheDB = table->getAntiCacheDB(chooseDB(block_size, m_migrate));
AntiCacheDB* antiCacheDB;
int tuple_length = -1;
bool needs_flush = false;

Expand All @@ -571,6 +567,12 @@ bool AntiCacheEvictionManager::evictBlockToDisk(PersistentTable *table, const lo
for(int i = 0; i < num_blocks; i++)
{

// get the AntiCacheDB instance from the executorContext
// For now use the single AntiCacheDB from PersistentTable but in the future, this
// method to get the AntiCacheDB will have to choose which AntiCacheDB from to
// evict to
antiCacheDB = table->getAntiCacheDB(chooseDB(block_size, m_migrate));

// get the LS16B and send that to the antiCacheDB
uint16_t _block_id = antiCacheDB->nextBlockId();

Expand Down Expand Up @@ -661,7 +663,7 @@ bool AntiCacheEvictionManager::evictBlockToDisk(PersistentTable *table, const lo
table->name().c_str(), num_tuples_evicted);

// Only write out a bock if there are tuples in it
if (num_tuples_evicted >= 0) {
if (num_tuples_evicted > 0) {
std::vector<int> numTuples;
numTuples.push_back(num_tuples_evicted);
block.writeHeader(numTuples);
Expand All @@ -686,6 +688,7 @@ bool AntiCacheEvictionManager::evictBlockToDisk(PersistentTable *table, const lo
// TODO: make this look like
// block.flush();
// antiCacheDB->writeBlock(block);
VOLT_DEBUG("about to write block %x to acid %d", _block_id, antiCacheDB->getACID());
antiCacheDB->writeBlock(table->name(),
_block_id,
num_tuples_evicted,
Expand All @@ -696,7 +699,7 @@ bool AntiCacheEvictionManager::evictBlockToDisk(PersistentTable *table, const lo

bool reused = table->removeUnevictedBlockID(block_id);
if (reused) {
VOLT_INFO("Reusing block_id 0x%x, should be safe", block_id);
VOLT_DEBUG("Reusing block_id 0x%x, should be safe", block_id);
} else {
VOLT_DEBUG("First time block_id 0x%x has been used", block_id);
}
Expand Down Expand Up @@ -781,7 +784,7 @@ bool AntiCacheEvictionManager::evictBlockToDiskInBatch(PersistentTable *table, P
// evictedTable->name().c_str(), evictedTable->schema()->debug().c_str());

// get the AntiCacheDB instance from the executorContext
AntiCacheDB* antiCacheDB = table->getAntiCacheDB(chooseDB(block_size, m_migrate));
AntiCacheDB* antiCacheDB;
int tuple_length = -1;
bool needs_flush = false;

Expand Down Expand Up @@ -822,6 +825,7 @@ bool AntiCacheEvictionManager::evictBlockToDiskInBatch(PersistentTable *table, P
// VOLT_INFO("Printing child's LRU chain");
// this->printLRUChain(childTable, 4, true);
// get a unique block id from the executorContext
antiCacheDB = table->getAntiCacheDB(chooseDB(block_size, m_migrate));
uint16_t _block_id = antiCacheDB->nextBlockId();
// find out whether this tier blocks and set a flag (bit 19)
// then shift 3b for the ACID (8 levels)
Expand Down Expand Up @@ -1343,6 +1347,7 @@ int32_t AntiCacheEvictionManager::migrateBlock(int32_t block_id, AntiCacheDB* ds
int32_t new_block_id = 0;

if (dstDB->getFreeBlocks() == 0) {
VOLT_WARN("Our destination is full!");
throw FullBackingStoreException((uint32_t)block_id, (uint32_t)dstDB->getACID());
}

Expand Down Expand Up @@ -1423,7 +1428,7 @@ int32_t AntiCacheEvictionManager::migrateLRUBlock(AntiCacheDB* srcDB, AntiCacheD
return (int32_t) _new_block_id;
}


VOLT_DEBUG("migrating LRU block");
AntiCacheBlock* block = srcDB->getLRUBlock();
int16_t _block_id = block->getBlockId();
int32_t block_id = (int32_t)_block_id;
Expand Down Expand Up @@ -1467,7 +1472,7 @@ int32_t AntiCacheEvictionManager::migrateLRUBlock(AntiCacheDB* srcDB, AntiCacheD
VOLT_TRACE("Updating tuple blockid from %8x to %8x", block_id, new_block_id);
}
}
VOLT_DEBUG("updated %u migrated tuples [#%8x -> #%8x]", updated, block_id, new_block_id);
VOLT_INFO("updated %u migrated tuples [#%8x -> #%8x]", updated, block_id, new_block_id);
} else {
VOLT_WARN("No evicted table! If this is an EE test, shouldn't be a problem");
}
Expand Down
8 changes: 5 additions & 3 deletions src/ee/anticache/NVMAntiCacheDB.cpp
View file
Original file line number Diff line number Diff line change
Expand Up @@ -196,6 +196,7 @@ void NVMAntiCacheDB::writeBlock(const std::string tableName,
const char* data,
const long size) {

VOLT_TRACE("free blocks: %d", getFreeBlocks());
if (getFreeBlocks() == 0) {
VOLT_WARN("No free space in ACID %d for blockid %u with blocksize %ld",
m_ACID, blockId, size);
Expand Down Expand Up @@ -280,14 +281,15 @@ uint16_t NVMAntiCacheDB::getFreeNVMBlockIndex() {

if(m_NVMBlockFreeList.size() > 0) {
free_index = m_NVMBlockFreeList.back();
VOLT_INFO("popping %u from list of size: %d", free_index, (int)m_NVMBlockFreeList.size());
VOLT_DEBUG("popping %u from list of size: %d", free_index, (int)m_NVMBlockFreeList.size());
m_NVMBlockFreeList.pop_back();
} else {
if (m_nextFreeBlock == getMaxBlocks()) {
VOLT_WARN("Backing store full m_nextFreeBlock %d == max %d", m_nextFreeBlock, getMaxBlocks());
throw FullBackingStoreException(0, m_nextFreeBlock);
} else {
free_index = m_nextFreeBlock;
VOLT_INFO("no reusable blocks (size: %d), using index %u", (int)m_NVMBlockFreeList.size(), free_index);
VOLT_DEBUG("no reusable blocks (size: %d), using index %u", (int)m_NVMBlockFreeList.size(), free_index);
++m_nextFreeBlock;
}
}
Expand All @@ -299,7 +301,7 @@ uint16_t NVMAntiCacheDB::getFreeNVMBlockIndex() {

void NVMAntiCacheDB::freeNVMBlock(uint16_t index) {
m_NVMBlockFreeList.push_back(index);
VOLT_INFO("list size: %d back: %u", (int)m_NVMBlockFreeList.size(), m_NVMBlockFreeList.back());
VOLT_DEBUG("list size: %d back: %u", (int)m_NVMBlockFreeList.size(), m_NVMBlockFreeList.back());
//m_blockIndex--;
}
}

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