Thursday, May 3, 2012

What the real online storage should be

Back in 2004, I was looking for online storage products, but I didn't find one. After a while, google launched google docs. I was happy with it at the beginning, as it allowed me to access my files anywhere as long as I have access to internet. As I put more files online, I feel frustrated as the user interface of google doc is not friendly at all. Also, I could not edit my files if there is no internet access, and the space is not big enough to store all my pictures. After a few frustrations due to intermittent internet loss, I finally gave up and switched to skydrive.

I have a free dropbox account, I don't use it much. I got to know it as my friends try to share files with me. The hesitation is due to its strange synchronization protocol and the space usage. Piaw and I shared a file on it and were editing the file at the same time, we ended up with a lot of versions of the file and I could not recognize which one to pick or how to integrate them. It is really frustrating. I prefer it has a simple locking algorithm: when one opens the file for write, just lock the file and don't give other users the write permission until the lock is released. Furthermore, all versions of the file occupies both the online storage space and the local storage space. So I mark dropbox as a file sharing tool, not a real online storage solution. Google just launched gdrive, the experience of sharing files is even more hilarious. First one receives a notification in the email about the sharing of the file, one needs to click the link in the email to accept the sharing. However the story doesn't really end here, the shared files are not in mydrive yet, I still need to drag it to mydrive folder in the web browser first, then it shows up at local copy mydrive folder. It doesn't really do anything particular for concurrent writes. It just gives out an unresolvable error. The local skydrive folder doesn't contain the shared folder at all, so one can only open the shared files by web browser. It also means when there is no internet access, the shared files are not accessible at all. Oh my, what is the local skydrive for then!

For real online storage products, I expect:
1. All my files are safely stored, it is not a backup of my local files. It has the complete collection of all my files. Technically, the online storage is a layer after the local storage. The local storage act as a cache layer for the online storage.   
2. If there is an internet access, I can access my files. So I don't need to carry a copy.
3. If I make some changes for a file while I am offline, the changes can be transparently synced when the internet access comes back and I don't need to do it manually.
4. It is easy to share. One can easily access my files by the web. The file can be write semi-concurrently at least. The synchronization work should be completely transparent to the user. 

For now, none of dropbox, gdrive, skydrive has done all of this.  Skydrive keeps a complete copy of all files locally.  If one buys 1TB of space, one will have 1TB of complete copy locally. This idea is just so wrong. For both dropbox and gdrive, one can specify which folders to be synced locally. It is kind of dilemma here. If one doesn't specify any folders, with default, one has the complete copy locally which may consume a lot of space. If one specifies which one to be synced to local, when a new folder created or shared, one needs to make a decision if it should be synced locally or not and also need to do some work to do that. If one file or folder occupies 1TB of space, one doesn't want to have 1TB of complete copy locally. So the user needs to think hard to decide which files or folders to be cached. The sharing implementation is quite awkward both in skydrive and gdrive. Overall, dropbox is better than gdrive and skydrive, but it is just a sharing tool, not really an online storage solution.

For an online storage solution, theoretically,  I would imagine it is adding a layer to the system. The local storage acts as the cache layer for the online storage, and the system now has five layers: CPU, cache(L1, L2, L3 caches), RAM, local disk, online storage.  The relationship of local storage to online storage is like memory to local disk. If internet access is not available, one could not access some files. It is challenging to design an intelligent caching algorithms to let users have more pleasant experience when the internet is not accessible. The caching algorithm can combine MRU (most recently used), MA (mostly accessed), and prefech files according the user's access pattern. To manage shared files and deal with concurrent writes, it is a classical problem and there are many solutions out there, like single writer locking protocol, or snoopy protocol.

Thursday, April 26, 2012

About Traveling with Boat - Some experiences from BVI

Piaw's blog about visiting BVI ( caught a lot of attention from his friends. Sometime, people even come to ask me about the experiences to verify if it is really great and worthwhile for a visit.  Most time people show interests and passion to go but are afraid of being bored on a boat all the time.

For me, one week is pretty doable.  For the longer stay, I would like to plan well in advance to spend more time on land during the day. It may sound a little crazy to stay on a boat for one week or longer, but the truth is that one don't really stay on the boat that long during the trip.

For example, an aggressive schedule of a day could look like:
7am: get up, prepare breakfast, and have breakfast while the boat is moving to the next site.
around 9am or 10am: get to the site that could be a beach or a diving place, do some swimming, snorkeling, diving, walking around beach. After these activities, it is near noon.
around noon: have a light lunch, prepare to go to the next site.
2pm: arrive a new site, if one still feels energetic, go swimming, etc. if not, have a tea or drink on the beach, do some reading, or just lie on the beach bathing in the sun, or do leisurely walking. If it is a seasonable size island, one also can hang out around the bar, shops,  do some grocery shopping, laundry etc.
6pm: start to prepare dinner on the boat and have dinner while watching terrific sunsets.
8pm: while watching the moon rising,  have some fun talking at the starry night.This ends of the day.

For a more leisurely and family-oriented day, one can plan to visit one island a day or spend two days on one island. It will still be a lot of fun by doing swimming, snorkeling, kayaking, board paddling, bathing in the sun on the beach, walking on the beach to see the sunset. The good thing to visit with a boat instead of a cruise ship is that you will have the feeling that the whole beach is just yours. It is so tranquil, that is the vacation one dreams. As the cruise ship doesn't go to those small islands or small beaches. Even going to a popular place, with a boat you can plan well to arrive earlier to avoid the big crowd.

While traveling with the boat, the feeling of on the boat is just the time while sailing that is just 2 or 4 hours a day. At night, at least for me, I don't have any trouble to fall asleep at all. The bed is cozy, but I like it as it is firm. Also as I have done so much activities during the day, I have a sound sleep every night.

One thing that really bothers me is the bad smell of the toilet on the boat. The shower space is small too. I hate to do push up and down to clean the toilet. I like to have hot water for showers. On the boat one needs to be cautious about the water usage and the electricity usage. Sometimes we have shortage on hot water. But if one plans well, like scheduling filling water tank every two days, it should be no problem with the water.

So, I will say, abstractly, doing islands hopping with a boat is more like traveling with RV. If you don't mind to sacrifice just a little comfort of the modern world, you will have a great experience to explore the nature with the ancient art.

Monday, April 23, 2012

Hiking Trails in Bayarea

Russian Ridge Trails: it has more flexibilities here. The road is well maintained, not difficult at all. One can take an easy hiking for 3-4 miles or take longer ones, like 10/22 miles. The view is fantastic in a sunny day. Highly recommended. Stevenson beach trail: it has nice view of stevenson beach. Most of areas are shaded and well maintained. If you come at the right time, it could have wild flowers and creeks, small water falls. The view of stevenson beach is unbeatable. Moderate difficulty. During rain season, the some of the road could be muddy. Diablo Hike: it is difficult just as the name. Most of the trails have sharp up/downs, but still doable with right shoes. Some part of the view is pretty nice.

Wednesday, March 21, 2012

Visit Half Moon Bay

We thought today was perfect to visit Half Moon Bay, but when we got there it was still a little foggy. Around 10:30am, we arrived at McNee Ranch State Park. There is a 8-mile long half-loop hiking trail. We took part of it. We started from one parking lot and ended at the other parking lot. It took us around one hour. Luckily when we were at the scenic outlook point, the fog went away and the view is really terrific. One could see the big waves, the ocean, even some rainbows caused by the waves clearly. It is a really nice hiking trail with beautiful views.

Around noon, we went to Pescadero and bought a fresh Artichoke loaf from Norm's Marke (Arcangeli Grocery). Both my mom and Piaw love that bread a lot. We had a light picnic at the back of the grocery store. The picnic area is always pretty and cheerful. This is the third time I have that bread at that picnic area. Then we drove to Pillar Point Harbor, as I am always fascinated by the lively caught Dungeness crabs. At first we saw a shop just at the entrance to the harbor selling crabs at $9 per lb. I ever did some research, it was said that the fishermen usually sell at $6 per lb. So we walked down toward the harbor. It is quite nice that there is a bulletin board marking which port is selling crabs or fishes. We located the boat and bought the lively crabs back home. It is really yummy as even my frugal parents said it was worth the money. If you want to have the crabs caught on the same day, you need to come around 3:30 or so. As the fishermen just come back around that time. The just caught crabs tastes even better.

Sunday, March 11, 2012

Oh Yer ... Got my Open Water Referral

In general, it should not be hard to get a diving certificate. But for me, who hasn't done exercise for a year and haven't done swimming for many years as a poor swimmer, it is really a challenge. While trying to book the class with a diving shop close to our place, my friend, Cindy, told me a even cheaper place, Aquatic Discovery. I didn't do any research about this shop. Just called and signed up for the class.
1. bough my personal gears: snorkel, mask, wet suit, fins, boots, gloves at the local store.
2. read PADI diving book. If you are like me who feel bored easily with this "technical reading", just do at least summary, review, and quiz part right before the class.
3. I watched the video just the day before the class. I would recommend to watch the video before reading the book and watch another time after reading the book and right before the class.
4. the exam is quite easy to pass as long as you have done/understood all the chapter reviews and quiz.
5. the pool part is not hard in theory, but one could have mental or psychology block. for me, when the instructor asked me to jump into the pool, I was scared at the beginning. I know in theory, it should be fine. Then I just jumped, it works!
My rule of thumb about pool part is keeping breathing through the regulator. As long as you have air and the regulator works, relax ...

1. My pool sessions were done in an outdoor swimming pool. Though it is heated, I still feel cold after a hour or so. Being cold is distracting. So either do the ppol session in an indoor swimming pool or in summer.
2. For Aquatic Discovery, it doesn't have its own swimming pool, it is a hassle to put tank into the care, get it out of the car, and carry to the pool side. It will be much less work and stressful, if the shop has its own swimming pool. But I guess, the price may be more expensive to account that.

Sunday, February 19, 2012

Visiting Hawaii

1. When you get to there, just pick up free tour books at the airport.  Tour books give you ideas about what to do, where to visit, and have coupons too. After reading a few of them, you will know all the best places you may visit and plan them ahead.
2. Book boat tours as earlier as possible as it gets filled up soon and weather may change.
3. Bring or prepare your own snorkeling/diving gears. At least, buy a good mask. I have completely different experiences with different masks. The one from costco doesn't work well. It does leak water in, and the lens gets blurred. Go to a local dive shop, try one, and ask the clerk to help you pick the right size with high VISIBILITY. Now I bought mine at Blue Water Aquatics on homestead. The prices of the mask is good, it is even cheaper than Amazon. Buy a pair of socks or booties to avoid that hard rocks or coral may scratch or hurt your feet while you try to stand up. Fins are not required, though it helps floating.
4. I like to live in residential area as it is less crowded, more family friendly, feeling more relaxed like being at home. I booked the places at It have more listings and price is much lower than other places too.
5. Hawaii still has Winter and Summer seasons. But don't let the words fool you. During Winter, one can still wear bikini:P. For summer, it is a better time for snorkeling, as the ocean is more calm, almost no waves. It is much more sunny I guess, so the visibility in the water is higher too. During winter, it has waves, so it is good for surfing.

1. Hana Drive. We did Hana Drive starting from Kahului airport and ending at Kihei area. Yer, we did a tour of east island and passed the broken road. I will say, it is a nice drive, but I may not do it again. We enjoyed the part of the broken road more, but the experience and scenery is similar to drive on Highway One passing Sausalito area. The sunset over the sea was terrific while driving along the broken road.

2. Snorkeling. I went out with a boat tour. It was supposed to go to Monokili but due to the bad weather, it went to Coral Garden instead. It is really beautiful under the water. I didn't do diving, so I don't have any experiences for that for now. For self-supported snorkeling, just locate the famous, expensive hotels, the best beaches or snorkeling sites are just in front of them and are open to public access. The beaches at Kaanapali area are terrific.

3. Wailea-Makena area are worth a visit too. A lot of new condos, hotels, nice beaches.

4. Visit Lahaina downtown to get some cheap tours. There are a lot of deals.

5. West Maui is always pleasant to live both in Winter and Summer. I guess Kilei area is a litte cheaper. As the Island is small, it really doesn't matter so much where you live for a few days visit. But if you would like to stay longer, it depends on what you like better, for snorkeling, west Maui. For surfing, around Kilei.

1. Great place for surfing and whale watching at winter time.
2. We stayed at Poipu area. Around Poipu beach park, it is a terrific place to watch sunset. For winter, it is a good place for both snorkeling and surfing. Though Kauai is small, it really doesn't matter where you live, one can easily drive from one side to the farthest side around one hour. Princeville area is pretty too, one may consider to stay there during summer time. The problem to live at Princeville is the driving. Look at the map carefully, the road at HaEna is an dead end.
3. Piaw did scuba diving with dive shop, he loves it.
4. Biking/walking on the paved road for 2-3 hours at Kappa area.
5. Visited Hanalai Bay, one can drive till the end of the road, then it reaches Haena. It is a nice swimming and snorkeling site.
6. Took boat tour to Napa Li Coast.