too many Segment.getKey() invocations about hugecollections-old HOT 3 OPEN

In most cases you can replace your use of HugeHashMap with ChronicleMap, could you try using ChronicleMap.

We are focusing most of our new development and support effort on ChronicleMap.

On 27 Oct 2014, at 10:49, Mesutcan Kurt [email protected] wrote:

I attached a profiler to my application and I saw that call tree:

https://cloud.githubusercontent.com/assets/439170/4789483/9a28a160-5dc5-11e4-9c8f-efffd151d9ba.png
I invoked Map.get() 8379 times and also net.openhft.collections.HugeHashMap$Segment.get is invoked same amount but Segment.getKey() is invoked 9.903.392 times.

Why getKey() invocation count is more about 1000 times than Map.get() count?

My get code:

for (Long key : cache.keySet()) {
sr = cache.get(key);

if (sr != null && sr.isDirty() && sr.isInDb()) {
    ++updateCount;

    sr.setClean();
    try {
        cache.put(key, sr);
    } catch (Exception e) {
    // discard
    }
}

}

—
Reply to this email directly or view it on GitHub #45.

from hugecollections-old.

If you want to iterate over the entries of any Map (not just ours) the most
efficient means is to use entrySet()

e.g.

for (Map.Entry<Long, SR> entry: cache.entrySet()) {

as you can see there is no need to lookup the entry via get()

BTW We have a means of efficiently persisting a Map to a JDBC connection,
perhaps you try this means of "replication"

On 27 October 2014 10:49, Mesutcan Kurt [email protected] wrote:

I attached a profiler to my application and I saw that call tree:

[image: image]
https://cloud.githubusercontent.com/assets/439170/4789483/9a28a160-5dc5-11e4-9c8f-efffd151d9ba.png

I invoked Map.get() 8379 times and also
net.openhft.collections.HugeHashMap$Segment.get is invoked same amount but
Segment.getKey() is invoked 9.903.392 times.

Why getKey() invocation count is more about 1000 times than Map.get()
count?

My get code:

for (Long key : cache.keySet()) {
sr = cache.get(key);

if (sr != null && sr.isDirty() && sr.isInDb()) {
    ++updateCount;

    sr.setClean();
    try {
        cache.put(key, sr);
    } catch (Exception e) {
    // discard
    }
}}

—
Reply to this email directly or view it on GitHub
#45.

from hugecollections-old.

BTW This could happen if you HugeHashMap is very full. (i.e. it is heavily
loaded compared to it's capacity)
When this happens, you might find a very large number of lookups are
performed to find each key.

On 27 October 2014 10:49, Mesutcan Kurt [email protected] wrote:

I attached a profiler to my application and I saw that call tree:

[image: image]
https://cloud.githubusercontent.com/assets/439170/4789483/9a28a160-5dc5-11e4-9c8f-efffd151d9ba.png

I invoked Map.get() 8379 times and also
net.openhft.collections.HugeHashMap$Segment.get is invoked same amount but
Segment.getKey() is invoked 9.903.392 times.

Why getKey() invocation count is more about 1000 times than Map.get()
count?

My get code:

for (Long key : cache.keySet()) {
sr = cache.get(key);

if (sr != null && sr.isDirty() && sr.isInDb()) {
    ++updateCount;

    sr.setClean();
    try {
        cache.put(key, sr);
    } catch (Exception e) {
    // discard
    }
}}

—
Reply to this email directly or view it on GitHub
#45.

from hugecollections-old.